64157121 has 30 divisors (see below), whose sum is σ = 108146610. Its totient is φ = 36648864.

The previous prime is 64157113. The next prime is 64157141. The reversal of 64157121 is 12175146.

It is a happy number.

64157121 is a `hidden beast` number, since 641 + 5 + 7 + 12 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 34574400 + 29582721 = 5880^2 + 5439^2 .

It is not a de Polignac number, because 64157121 - 2³ = 64157113 is a prime.

It is a super-2 number, since 2×64157121² = 8232272350017282, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (64157101) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 20125 + ... + 23093.

It is an arithmetic number, because the mean of its divisors is an integer number (3604887).

Almost surely, 2^64157121 is an apocalyptic number.

It is an amenable number.

64157121 is a deficient number, since it is larger than the sum of its proper divisors (43989489).

64157121 is an equidigital number, since it uses as much as digits as its factorization.

64157121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3003 (or 2979 counting only the distinct ones).

The product of its digits is 1680, while the sum is 27.

The square root of 64157121 is about 8009.8140427853. The cubic root of 64157121 is about 400.3270679102.

The spelling of 64157121 in words is "sixty-four million, one hundred fifty-seven thousand, one hundred twenty-one".