644527413 has 24 divisors (see below), whose sum is σ = 979150848. Its totient is φ = 407750112.

The previous prime is 644527397. The next prime is 644527427. The reversal of 644527413 is 314725446.

644527413 is a `hidden beast` number, since 644 + 5 + 2 + 7 + 4 + 1 + 3 = 666.

It is not a de Polignac number, because 644527413 - 2⁴ = 644527397 is a prime.

It is a super-2 number, since 2×644527413² = 830831172216945138, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644527463) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14031 + ... + 38547.

It is an arithmetic number, because the mean of its divisors is an integer number (40797952).

Almost surely, 2^644527413 is an apocalyptic number.

It is an amenable number.

644527413 is a deficient number, since it is larger than the sum of its proper divisors (334623435).

644527413 is a wasteful number, since it uses less digits than its factorization.

644527413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24673 (or 24670 counting only the distinct ones).

The product of its digits is 80640, while the sum is 36.

The square root of 644527413 is about 25387.5444460468. The cubic root of 644527413 is about 863.8011896280.

The spelling of 644527413 in words is "six hundred forty-four million, five hundred twenty-seven thousand, four hundred thirteen".