21154025515263 has 24 divisors (see below), whose sum is σ = 28410835825680. Its totient is φ = 14000624709120.

The previous prime is 21154025515253. The next prime is 21154025515349. The reversal of 21154025515263 is 36251552045112.

It is a happy number.

It is not a de Polignac number, because 21154025515263 - 2³⁶ = 21085306038527 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21154025515243) 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, 53475783 + ... + 53869911.

It is an arithmetic number, because the mean of its divisors is an integer number (1183784826070).

Almost surely, 2^{21154025515263} is an apocalyptic number.

21154025515263 is a deficient number, since it is larger than the sum of its proper divisors (7256810310417).

21154025515263 is an equidigital number, since it uses as much as digits as its factorization.

21154025515263 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 394987 (or 394790 counting only the distinct ones).

The product of its (nonzero) digits is 360000, while the sum is 42.

The spelling of 21154025515263 in words is "twenty-one trillion, one hundred fifty-four billion, twenty-five million, five hundred fifteen thousand, two hundred sixty-three".