644960435 has 32 divisors (see below), whose sum is σ = 920557440. Its totient is φ = 424424448.

The previous prime is 644960413. The next prime is 644960471. The reversal of 644960435 is 534069446.

It is not a de Polignac number, because 644960435 - 2¹² = 644956339 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 644960392 and 644960401.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 173759 + ... + 177431.

It is an arithmetic number, because the mean of its divisors is an integer number (28767420).

Almost surely, 2^644960435 is an apocalyptic number.

644960435 is a deficient number, since it is larger than the sum of its proper divisors (275597005).

644960435 is a wasteful number, since it uses less digits than its factorization.

644960435 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3887.

The product of its (nonzero) digits is 311040, while the sum is 41.

The square root of 644960435 is about 25396.0712512782. The cubic root of 644960435 is about 863.9945929267.

The spelling of 644960435 in words is "six hundred forty-four million, nine hundred sixty thousand, four hundred thirty-five".