23513635021 has 4 divisors (see below), whose sum is σ = 23557098844. Its totient is φ = 23470171200.

The previous prime is 23513634973. The next prime is 23513635027. The reversal of 23513635021 is 12053631532.

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

It can be written as a sum of positive squares in 2 ways, for example, as 10092412521 + 13421222500 = 100461^2 + 115850^2 .

It is a cyclic number.

It is not a de Polignac number, because 23513635021 - 2¹⁵ = 23513602253 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 (23513635027) 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, 21731100 + ... + 21732181.

It is an arithmetic number, because the mean of its divisors is an integer number (5889274711).

Almost surely, 2^23513635021 is an apocalyptic number.

It is an amenable number.

23513635021 is a deficient number, since it is larger than the sum of its proper divisors (43463823).

23513635021 is an equidigital number, since it uses as much as digits as its factorization.

23513635021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43463822.

The product of its (nonzero) digits is 16200, while the sum is 31.

The spelling of 23513635021 in words is "twenty-three billion, five hundred thirteen million, six hundred thirty-five thousand, twenty-one".