21156546611013 has 24 divisors (see below), whose sum is σ = 31033227875328. Its totient is φ = 12811009200000.

The previous prime is 21156546610967. The next prime is 21156546611021. The reversal of 21156546611013 is 31011664565112.

It is a happy number.

It is not a de Polignac number, because 21156546611013 - 2¹² = 21156546606917 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21156546611413) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24900388 + ... + 25736013.

It is an arithmetic number, because the mean of its divisors is an integer number (1293051161472).

Almost surely, 2^{21156546611013} is an apocalyptic number.

It is an amenable number.

21156546611013 is a deficient number, since it is larger than the sum of its proper divisors (9876681264315).

21156546611013 is a wasteful number, since it uses less digits than its factorization.

21156546611013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50637577 (or 50637566 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 42.

The spelling of 21156546611013 in words is "twenty-one trillion, one hundred fifty-six billion, five hundred forty-six million, six hundred eleven thousand, thirteen".