642654457 has 4 divisors (see below), whose sum is σ = 645155316. Its totient is φ = 640153600.

The previous prime is 642654427. The next prime is 642654511. The reversal of 642654457 is 754456246.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 333281536 + 309372921 = 18256^2 + 17589^2 .

It is a cyclic number.

It is not a de Polignac number, because 642654457 - 2⁷ = 642654329 is a prime.

It is a super-2 number, since 2×642654457² = 826009502203929698, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642654427) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1250044 + ... + 1250557.

It is an arithmetic number, because the mean of its divisors is an integer number (161288829).

Almost surely, 2^642654457 is an apocalyptic number.

It is an amenable number.

642654457 is a deficient number, since it is larger than the sum of its proper divisors (2500859).

642654457 is a wasteful number, since it uses less digits than its factorization.

642654457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2500858.

The product of its digits is 806400, while the sum is 43.

The square root of 642654457 is about 25350.6303077458. The cubic root of 642654457 is about 862.9636605807.

The spelling of 642654457 in words is "six hundred forty-two million, six hundred fifty-four thousand, four hundred fifty-seven".