221642673556531 has 16 divisors (see below), whose sum is σ = 226002571361280. Its totient is φ = 217303450449120.

The previous prime is 221642673556517. The next prime is 221642673556547. The reversal of 221642673556531 is 135655376246122.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 221642673556531 - 2²³ = 221642665167923 is a prime.

It is a super-2 number, since 2×221642673556531² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221642673556561) 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, 42953125 + ... + 47835721.

It is an arithmetic number, because the mean of its divisors is an integer number (14125160710080).

Almost surely, 2^{221642673556531} is an apocalyptic number.

221642673556531 is a deficient number, since it is larger than the sum of its proper divisors (4359897804749).

221642673556531 is a wasteful number, since it uses less digits than its factorization.

221642673556531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4884714.

The product of its digits is 54432000, while the sum is 58.

The spelling of 221642673556531 in words is "two hundred twenty-one trillion, six hundred forty-two billion, six hundred seventy-three million, five hundred fifty-six thousand, five hundred thirty-one".