221708086137651 has 32 divisors (see below), whose sum is σ = 296869286633728. Its totient is φ = 147176855729280.

The previous prime is 221708086137617. The next prime is 221708086137679. The reversal of 221708086137651 is 156731680807122.

It is not a de Polignac number, because 221708086137651 - 2²² = 221708081943347 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221708086137591 and 221708086137600.

It is not an unprimeable number, because it can be changed into a prime (221708086137691) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12520919940 + ... + 12520937646.

It is an arithmetic number, because the mean of its divisors is an integer number (9277165207304).

Almost surely, 2^{221708086137651} is an apocalyptic number.

221708086137651 is a deficient number, since it is larger than the sum of its proper divisors (75161200496077).

221708086137651 is a wasteful number, since it uses less digits than its factorization.

221708086137651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26851.

The product of its (nonzero) digits is 6773760, while the sum is 57.

The spelling of 221708086137651 in words is "two hundred twenty-one trillion, seven hundred eight billion, eighty-six million, one hundred thirty-seven thousand, six hundred fifty-one".