57720647 has 2 divisors, whose sum is σ = 57720648. Its totient is φ = 57720646.

The previous prime is 57720617. The next prime is 57720673. The reversal of 57720647 is 74602775.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 57720647 - 2⁶ = 57720583 is a prime.

It is a Chen prime.

It is equal to p_3434789 and since 57720647 and 3434789 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 57720647.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (57720617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28860323 + 28860324.

It is an arithmetic number, because the mean of its divisors is an integer number (28860324).

Almost surely, 2^57720647 is an apocalyptic number.

57720647 is a deficient number, since it is larger than the sum of its proper divisors (1).

57720647 is an equidigital number, since it uses as much as digits as its factorization.

57720647 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 82320, while the sum is 38.

The square root of 57720647 is about 7597.4105457057. The cubic root of 57720647 is about 386.4652032980.

The spelling of 57720647 in words is "fifty-seven million, seven hundred twenty thousand, six hundred forty-seven".