647857401 has 4 divisors (see below), whose sum is σ = 863809872. Its totient is φ = 431904932.

The previous prime is 647857391. The next prime is 647857409. The reversal of 647857401 is 104758746.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 647857401 - 2¹⁸ = 647595257 is a prime.

It is not an unprimeable number, because it can be changed into a prime (647857409) 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, 107976231 + ... + 107976236.

It is an arithmetic number, because the mean of its divisors is an integer number (215952468).

Almost surely, 2^647857401 is an apocalyptic number.

It is an amenable number.

647857401 is a deficient number, since it is larger than the sum of its proper divisors (215952471).

647857401 is a wasteful number, since it uses less digits than its factorization.

647857401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215952470.

The product of its (nonzero) digits is 188160, while the sum is 42.

The square root of 647857401 is about 25453.0430597208. The cubic root of 647857401 is about 865.2862611862.

The spelling of 647857401 in words is "six hundred forty-seven million, eight hundred fifty-seven thousand, four hundred one".