21014055520 has 24 divisors (see below), whose sum is σ = 49645706544. Its totient is φ = 8405622144.

The previous prime is 21014055481. The next prime is 21014055533. The reversal of 21014055520 is 2555041012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65668764 + ... + 65669083.

It is an arithmetic number, because the mean of its divisors is an integer number (2068571106).

Almost surely, 2^21014055520 is an apocalyptic number.

21014055520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21014055520 is an abundant number, since it is smaller than the sum of its proper divisors (28631651024).

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

21014055520 is a wasteful number, since it uses less digits than its factorization.

21014055520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131337862 (or 131337854 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 25.

Adding to 21014055520 its reverse (2555041012), we get a palindrome (23569096532).

The spelling of 21014055520 in words is "twenty-one billion, fourteen million, fifty-five thousand, five hundred twenty".