20996601520 has 20 divisors (see below), whose sum is σ = 48817098720. Its totient is φ = 8398640576.

The previous prime is 20996601499. The next prime is 20996601523. The reversal of 20996601520 is 2510669902.

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (20996601523) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 131228680 + ... + 131228839.

It is an arithmetic number, because the mean of its divisors is an integer number (2440854936).

Almost surely, 2^20996601520 is an apocalyptic number.

20996601520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20996601520 is an abundant number, since it is smaller than the sum of its proper divisors (27820497200).

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

20996601520 is a wasteful number, since it uses less digits than its factorization.

20996601520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262457532 (or 262457526 counting only the distinct ones).

The product of its (nonzero) digits is 58320, while the sum is 40.

The spelling of 20996601520 in words is "twenty billion, nine hundred ninety-six million, six hundred one thousand, five hundred twenty".