664742157 has 8 divisors (see below), whose sum is σ = 896281920. Its totient is φ = 438181920.

The previous prime is 664742137. The next prime is 664742167. The reversal of 664742157 is 751247466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 664742157 - 2²⁷ = 530524429 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664742137) 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, 1244569 + ... + 1245102.

It is an arithmetic number, because the mean of its divisors is an integer number (112035240).

Almost surely, 2^664742157 is an apocalyptic number.

It is an amenable number.

664742157 is a deficient number, since it is larger than the sum of its proper divisors (231539763).

664742157 is a wasteful number, since it uses less digits than its factorization.

664742157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2489763.

The product of its digits is 282240, while the sum is 42.

The square root of 664742157 is about 25782.5940704189. The cubic root of 664742157 is about 872.7390475339.

The spelling of 664742157 in words is "six hundred sixty-four million, seven hundred forty-two thousand, one hundred fifty-seven".