21557860933 has 8 divisors (see below), whose sum is σ = 24891551552. Its totient is φ = 18287669376.

The previous prime is 21557860903. The next prime is 21557861021. The reversal of 21557860933 is 33906875512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21557860933 - 2⁹ = 21557860421 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21557860903) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15874035 + ... + 15875392.

It is an arithmetic number, because the mean of its divisors is an integer number (3111443944).

Almost surely, 2^21557860933 is an apocalyptic number.

It is an amenable number.

21557860933 is a deficient number, since it is larger than the sum of its proper divisors (3333690619).

21557860933 is an equidigital number, since it uses as much as digits as its factorization.

21557860933 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31749531.

The product of its (nonzero) digits is 1360800, while the sum is 49.

The spelling of 21557860933 in words is "twenty-one billion, five hundred fifty-seven million, eight hundred sixty thousand, nine hundred thirty-three".