21620542645121 has 8 divisors (see below), whose sum is σ = 24709975842240. Its totient is φ = 18531305509968.

The previous prime is 21620542645057. The next prime is 21620542645171. The reversal of 21620542645121 is 12154624502612.

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 21620542645121 - 2⁶ = 21620542645057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21620542645171) 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, 48779111 + ... + 49220348.

It is an arithmetic number, because the mean of its divisors is an integer number (3088746980280).

Almost surely, 2^{21620542645121} is an apocalyptic number.

It is an amenable number.

21620542645121 is a deficient number, since it is larger than the sum of its proper divisors (3089433197119).

21620542645121 is an equidigital number, since it uses as much as digits as its factorization.

21620542645121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98030983.

The product of its (nonzero) digits is 230400, while the sum is 41.

The spelling of 21620542645121 in words is "twenty-one trillion, six hundred twenty billion, five hundred forty-two million, six hundred forty-five thousand, one hundred twenty-one".