15855777040 has 80 divisors (see below), whose sum is σ = 37206993600. Its totient is φ = 6283690496.

The previous prime is 15855777023. The next prime is 15855777059. The reversal of 15855777040 is 4077755851.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4193871 + ... + 4197649.

It is an arithmetic number, because the mean of its divisors is an integer number (465087420).

Almost surely, 2^15855777040 is an apocalyptic number.

15855777040 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 15855777040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18603496800).

15855777040 is an abundant number, since it is smaller than the sum of its proper divisors (21351216560).

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

15855777040 is a wasteful number, since it uses less digits than its factorization.

15855777040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4264 (or 4258 counting only the distinct ones).

The product of its (nonzero) digits is 1372000, while the sum is 49.

The spelling of 15855777040 in words is "fifteen billion, eight hundred fifty-five million, seven hundred seventy-seven thousand, forty".