20995697291920 has 320 divisors, whose sum is σ = 54410914353600. Its totient is φ = 7484157886464.

The previous prime is 20995697291903. The next prime is 20995697291953. The reversal of 20995697291920 is 2919279659902.

It can be written as a sum of positive squares in 32 ways, for example, as 19610584851456 + 1385112440464 = 4428384^2 + 1176908^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20995697291920.

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, 9156430294 + ... + 9156432586.

It is an arithmetic number, because the mean of its divisors is an integer number (170034107355).

Almost surely, 2^{20995697291920} is an apocalyptic number.

20995697291920 is a gapful number since it is divisible by the number (20) 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 20995697291920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27205457176800).

20995697291920 is an abundant number, since it is smaller than the sum of its proper divisors (33415217061680).

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

20995697291920 is a wasteful number, since it uses less digits than its factorization.

20995697291920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4102 (or 4096 counting only the distinct ones).

The product of its (nonzero) digits is 99202320, while the sum is 70.

The spelling of 20995697291920 in words is "twenty trillion, nine hundred ninety-five billion, six hundred ninety-seven million, two hundred ninety-one thousand, nine hundred twenty".