253215521421 has 16 divisors (see below), whose sum is σ = 341250720384. Its totient is φ = 166996859904.

The previous prime is 253215521413. The next prime is 253215521453. The reversal of 253215521421 is 124125512352.

It is not a de Polignac number, because 253215521421 - 2³ = 253215521413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (253215521411) 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, 479016 + ... + 857838.

It is an arithmetic number, because the mean of its divisors is an integer number (21328170024).

Almost surely, 2^253215521421 is an apocalyptic number.

It is an amenable number.

253215521421 is a deficient number, since it is larger than the sum of its proper divisors (88035198963).

253215521421 is a wasteful number, since it uses less digits than its factorization.

253215521421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381220.

The product of its digits is 24000, while the sum is 33.

The spelling of 253215521421 in words is "two hundred fifty-three billion, two hundred fifteen million, five hundred twenty-one thousand, four hundred twenty-one".