15566281440 has 48 divisors (see below), whose sum is σ = 49033788048. Its totient is φ = 4151008256.

The previous prime is 15566281399. The next prime is 15566281447. The reversal of 15566281440 is 4418266551.

It is a tau number, because it is divible by the number of its divisors (48).

It is a junction number, because it is equal to n+sod(n) for n = 15566281392 and 15566281401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15566281447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16214397 + ... + 16215356.

It is an arithmetic number, because the mean of its divisors is an integer number (1021537251).

Almost surely, 2^15566281440 is an apocalyptic number.

15566281440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15566281440 is an abundant number, since it is smaller than the sum of its proper divisors (33467506608).

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

15566281440 is a wasteful number, since it uses less digits than its factorization.

15566281440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32429771 (or 32429763 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 42.

The spelling of 15566281440 in words is "fifteen billion, five hundred sixty-six million, two hundred eighty-one thousand, four hundred forty".