11523666021 has 16 divisors (see below), whose sum is σ = 18034464384. Its totient is φ = 6406979904.

The previous prime is 11523666013. The next prime is 11523666023. The reversal of 11523666021 is 12066632511.

It is not a de Polignac number, because 11523666021 - 2³ = 11523666013 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11523666023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7414710 + ... + 7416263.

It is an arithmetic number, because the mean of its divisors is an integer number (1127154024).

Almost surely, 2^11523666021 is an apocalyptic number.

It is an amenable number.

11523666021 is a deficient number, since it is larger than the sum of its proper divisors (6510798363).

11523666021 is a wasteful number, since it uses less digits than its factorization.

11523666021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14831020.

The product of its (nonzero) digits is 12960, while the sum is 33.

The spelling of 11523666021 in words is "eleven billion, five hundred twenty-three million, six hundred sixty-six thousand, twenty-one".