1561001016450 has 48 divisors (see below), whose sum is σ = 3879040788000. Its totient is φ = 415432715520.

The previous prime is 1561001016397. The next prime is 1561001016493. The reversal of 1561001016450 is 546101001651.

It is a super-3 number, since 3×1561001016450³ (a number of 38 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10352679 + ... + 10502378.

It is an arithmetic number, because the mean of its divisors is an integer number (80813349750).

Almost surely, 2^{1561001016450} is an apocalyptic number.

1561001016450 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1561001016450 is an abundant number, since it is smaller than the sum of its proper divisors (2318039771550).

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

1561001016450 is a wasteful number, since it uses less digits than its factorization.

1561001016450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20855571 (or 20855566 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 30.

The spelling of 1561001016450 in words is "one trillion, five hundred sixty-one billion, one million, sixteen thousand, four hundred fifty".