53121981 has 8 divisors (see below), whose sum is σ = 77268384. Its totient is φ = 32195120.

The previous prime is 53121979. The next prime is 53121983. The reversal of 53121981 is 18912135.

It is an interprime number because it is at equal distance from previous prime (53121979) and next prime (53121983).

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 53121981 - 2¹ = 53121979 is a prime.

It is a super-2 number, since 2×53121981² = 5643889730728722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (53121983) 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, 804846 + ... + 804911.

It is an arithmetic number, because the mean of its divisors is an integer number (9658548).

Almost surely, 2^53121981 is an apocalyptic number.

It is an amenable number.

53121981 is a deficient number, since it is larger than the sum of its proper divisors (24146403).

53121981 is a wasteful number, since it uses less digits than its factorization.

53121981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1609771.

The product of its digits is 2160, while the sum is 30.

The square root of 53121981 is about 7288.4827639228. The cubic root of 53121981 is about 375.9165278905.

The spelling of 53121981 in words is "fifty-three million, one hundred twenty-one thousand, nine hundred eighty-one".