23021520551 has 4 divisors (see below), whose sum is σ = 23173981104. Its totient is φ = 22869060000.

The previous prime is 23021520503. The next prime is 23021520553. The reversal of 23021520551 is 15502512032.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23021520551 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 23021520551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23021520553) 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, 76230050 + ... + 76230351.

It is an arithmetic number, because the mean of its divisors is an integer number (5793495276).

Almost surely, 2^23021520551 is an apocalyptic number.

23021520551 is a deficient number, since it is larger than the sum of its proper divisors (152460553).

23021520551 is a wasteful number, since it uses less digits than its factorization.

23021520551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152460552.

The product of its (nonzero) digits is 3000, while the sum is 26.

The spelling of 23021520551 in words is "twenty-three billion, twenty-one million, five hundred twenty thousand, five hundred fifty-one".