21155165253013 has 8 divisors (see below), whose sum is σ = 23306860730016. Its totient is φ = 19041552882000.

The previous prime is 21155165252959. The next prime is 21155165253017. The reversal of 21155165253013 is 31035256155112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21155165253013 - 2³⁷ = 21017726299541 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21155165253017) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9520775331 + ... + 9520777552.

It is an arithmetic number, because the mean of its divisors is an integer number (2913357591252).

Almost surely, 2^{21155165253013} is an apocalyptic number.

It is an amenable number.

21155165253013 is a deficient number, since it is larger than the sum of its proper divisors (2151695477003).

21155165253013 is a wasteful number, since it uses less digits than its factorization.

21155165253013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19041552995.

The product of its (nonzero) digits is 135000, while the sum is 40.

The spelling of 21155165253013 in words is "twenty-one trillion, one hundred fifty-five billion, one hundred sixty-five million, two hundred fifty-three thousand, thirteen".