16233621561 has 24 divisors (see below), whose sum is σ = 24334521120. Its totient is φ = 10814630112.

The previous prime is 16233621539. The next prime is 16233621583. The reversal of 16233621561 is 16512633261.

16233621561 is a `hidden beast` number, since 1 + 6 + 2 + 33 + 62 + 1 + 561 = 666.

It is an interprime number because it is at equal distance from previous prime (16233621539) and next prime (16233621583).

It is not a de Polignac number, because 16233621561 - 2⁹ = 16233621049 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16233621461) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 324910 + ... + 371528.

It is an arithmetic number, because the mean of its divisors is an integer number (1013938380).

Almost surely, 2^16233621561 is an apocalyptic number.

It is an amenable number.

16233621561 is a deficient number, since it is larger than the sum of its proper divisors (8100899559).

16233621561 is an equidigital number, since it uses as much as digits as its factorization.

16233621561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48067 (or 48055 counting only the distinct ones).

The product of its digits is 38880, while the sum is 36.

The spelling of 16233621561 in words is "sixteen billion, two hundred thirty-three million, six hundred twenty-one thousand, five hundred sixty-one".