20155017520 has 80 divisors (see below), whose sum is σ = 52208229888. Its totient is φ = 7173144320.

The previous prime is 20155017481. The next prime is 20155017569. The reversal of 20155017520 is 2571055102.

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, 202294 + ... + 285013.

Almost surely, 2^20155017520 is an apocalyptic number.

20155017520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20155017520 is an abundant number, since it is smaller than the sum of its proper divisors (32053212368).

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

20155017520 is a wasteful number, since it uses less digits than its factorization.

20155017520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 487378 (or 487372 counting only the distinct ones).

The product of its (nonzero) digits is 3500, while the sum is 28.

The spelling of 20155017520 in words is "twenty billion, one hundred fifty-five million, seventeen thousand, five hundred twenty".