15540440520 has 256 divisors, whose sum is σ = 54738996480. Its totient is φ = 3487334400.

The previous prime is 15540440507. The next prime is 15540440549. The reversal of 15540440520 is 2504404551.

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 63 ways as a sum of consecutive naturals, for example, 1363164 + ... + 1374516.

It is an arithmetic number, because the mean of its divisors is an integer number (213824205).

Almost surely, 2^15540440520 is an apocalyptic number.

15540440520 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 15540440520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27369498240).

15540440520 is an abundant number, since it is smaller than the sum of its proper divisors (39198555960).

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

15540440520 is a wasteful number, since it uses less digits than its factorization.

15540440520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11456 (or 11452 counting only the distinct ones).

The product of its (nonzero) digits is 16000, while the sum is 30.

The spelling of 15540440520 in words is "fifteen billion, five hundred forty million, four hundred forty thousand, five hundred twenty".