1551809609028 has 384 divisors, whose sum is σ = 4855255695360. Its totient is φ = 419362790400.

The previous prime is 1551809608969. The next prime is 1551809609029. The reversal of 1551809609028 is 8209069081551.

1551809609028 is a `hidden beast` number, since 1 + 5 + 5 + 1 + 8 + 0 + 9 + 609 + 0 + 28 = 666.

It is a super-2 number, since 2×1551809609028² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (1551809609029) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 198513376 + ... + 198521192.

It is an arithmetic number, because the mean of its divisors is an integer number (12643895040).

Almost surely, 2^{1551809609028} is an apocalyptic number.

1551809609028 is a gapful number since it is divisible by the number (18) 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 1551809609028, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2427627847680).

1551809609028 is an abundant number, since it is smaller than the sum of its proper divisors (3303446086332).

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

1551809609028 is a wasteful number, since it uses less digits than its factorization.

1551809609028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8072 (or 8064 counting only the distinct ones).

The product of its (nonzero) digits is 1555200, while the sum is 54.

The spelling of 1551809609028 in words is "one trillion, five hundred fifty-one billion, eight hundred nine million, six hundred nine thousand, twenty-eight".