1554778615560 has 128 divisors (see below), whose sum is σ = 4738446812160. Its totient is φ = 408040774400.

The previous prime is 1554778615553. The next prime is 1554778615567. The reversal of 1554778615560 is 655168774551.

It is an interprime number because it is at equal distance from previous prime (1554778615553) and next prime (1554778615567).

It is a super-2 number, since 2×1554778615560² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a junction number, because it is equal to n+sod(n) for n = 1554778615494 and 1554778615503.

It is not an unprimeable number, because it can be changed into a prime (1554778615567) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4634695 + ... + 4958825.

It is an arithmetic number, because the mean of its divisors is an integer number (37019115720).

Almost surely, 2^{1554778615560} is an apocalyptic number.

1554778615560 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1554778615560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2369223406080).

1554778615560 is an abundant number, since it is smaller than the sum of its proper divisors (3183668196600).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1554778615560 is a wasteful number, since it uses less digits than its factorization.

1554778615560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324779 (or 324775 counting only the distinct ones).

The product of its (nonzero) digits is 35280000, while the sum is 60.

The spelling of 1554778615560 in words is "one trillion, five hundred fifty-four billion, seven hundred seventy-eight million, six hundred fifteen thousand, five hundred sixty".