64620431 has 4 divisors (see below), whose sum is σ = 64671552. Its totient is φ = 64569312.

The previous prime is 64620427. The next prime is 64620433. The reversal of 64620431 is 13402646.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13402646 = 2 ⋅6701323.

It is a cyclic number.

It is not a de Polignac number, because 64620431 - 2² = 64620427 is a prime.

It is a super-2 number, since 2×64620431² = 8351600205251522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64620431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64620433) 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, 23615 + ... + 26208.

It is an arithmetic number, because the mean of its divisors is an integer number (16167888).

Almost surely, 2^64620431 is an apocalyptic number.

64620431 is a deficient number, since it is larger than the sum of its proper divisors (51121).

64620431 is a wasteful number, since it uses less digits than its factorization.

64620431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51120.

The product of its (nonzero) digits is 3456, while the sum is 26.

The square root of 64620431 is about 8038.6834121018. The cubic root of 64620431 is about 401.2884101259.

The spelling of 64620431 in words is "sixty-four million, six hundred twenty thousand, four hundred thirty-one".