642511057 has 8 divisors (see below), whose sum is σ = 645354216. Its totient is φ = 639674112.

The previous prime is 642511027. The next prime is 642511069. The reversal of 642511057 is 750115246.

642511057 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 183223296 + 459287761 = 13536^2 + 21431^2 .

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 642511057 - 2¹⁵ = 642478289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642511007) 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, 429603 + ... + 431095.

It is an arithmetic number, because the mean of its divisors is an integer number (80669277).

Almost surely, 2^642511057 is an apocalyptic number.

It is an amenable number.

642511057 is a deficient number, since it is larger than the sum of its proper divisors (2843159).

642511057 is a wasteful number, since it uses less digits than its factorization.

642511057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3107.

The product of its (nonzero) digits is 8400, while the sum is 31.

The square root of 642511057 is about 25347.8018179092. The cubic root of 642511057 is about 862.8994694263.

The spelling of 642511057 in words is "six hundred forty-two million, five hundred eleven thousand, fifty-seven".