53121666 has 16 divisors (see below), whose sum is σ = 114416064. Its totient is φ = 16345104.

The previous prime is 53121661. The next prime is 53121671. The reversal of 53121666 is 66612135.

It is an interprime number because it is at equal distance from previous prime (53121661) and next prime (53121671).

It is a super-2 number, since 2×53121666² = 5643822797231112, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (53121661) 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, 340446 + ... + 340601.

It is an arithmetic number, because the mean of its divisors is an integer number (7151004).

Almost surely, 2^53121666 is an apocalyptic number.

53121666 is an abundant number, since it is smaller than the sum of its proper divisors (61294398).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

53121666 is a wasteful number, since it uses less digits than its factorization.

53121666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 681065.

The product of its digits is 6480, while the sum is 30.

The square root of 53121666 is about 7288.4611544550. The cubic root of 53121666 is about 375.9157848588.

The spelling of 53121666 in words is "fifty-three million, one hundred twenty-one thousand, six hundred sixty-six".