21154554025 has 36 divisors (see below), whose sum is σ = 28856844016. Its totient is φ = 15372482400.

The previous prime is 21154554023. The next prime is 21154554067. The reversal of 21154554025 is 52045545112.

It is not a de Polignac number, because 21154554025 - 2¹ = 21154554023 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21154554023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 5282674 + ... + 5286676.

Almost surely, 2^21154554025 is an apocalyptic number.

21154554025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21154554025 is a deficient number, since it is larger than the sum of its proper divisors (7702289991).

21154554025 is a wasteful number, since it uses less digits than its factorization.

21154554025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5782 (or 5766 counting only the distinct ones).

The product of its (nonzero) digits is 40000, while the sum is 34.

The spelling of 21154554025 in words is "twenty-one billion, one hundred fifty-four million, five hundred fifty-four thousand, twenty-five".