640890247625 has 16 divisors (see below), whose sum is σ = 834606294912. Its totient is φ = 490420361200.

The previous prime is 640890247577. The next prime is 640890247631. The reversal of 640890247625 is 526742098046.

It is a happy number.

It is not a de Polignac number, because 640890247625 - 2²² = 640886053321 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 111456299 + ... + 111462048.

It is an arithmetic number, because the mean of its divisors is an integer number (52162893432).

Almost surely, 2^640890247625 is an apocalyptic number.

It is an amenable number.

640890247625 is a deficient number, since it is larger than the sum of its proper divisors (193716047287).

640890247625 is a wasteful number, since it uses less digits than its factorization.

640890247625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222918385 (or 222918375 counting only the distinct ones).

The product of its (nonzero) digits is 5806080, while the sum is 53.

The spelling of 640890247625 in words is "six hundred forty billion, eight hundred ninety million, two hundred forty-seven thousand, six hundred twenty-five".