21251550527 has 4 divisors (see below), whose sum is σ = 21359426616. Its totient is φ = 21143674440.

The previous prime is 21251550487. The next prime is 21251550533. The reversal of 21251550527 is 72505515212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21251550527 - 2³⁴ = 4071681343 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 (21251550427) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53937749 + ... + 53938142.

It is an arithmetic number, because the mean of its divisors is an integer number (5339856654).

Almost surely, 2^21251550527 is an apocalyptic number.

21251550527 is a deficient number, since it is larger than the sum of its proper divisors (107876089).

21251550527 is a wasteful number, since it uses less digits than its factorization.

21251550527 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107876088.

The product of its (nonzero) digits is 35000, while the sum is 35.

The spelling of 21251550527 in words is "twenty-one billion, two hundred fifty-one million, five hundred fifty thousand, five hundred twenty-seven".