64902639 has 4 divisors (see below), whose sum is σ = 86536856. Its totient is φ = 43268424.

The previous prime is 64902599. The next prime is 64902641. The reversal of 64902639 is 93620946.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 64902639 - 2¹² = 64898543 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 64902597 and 64902606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64902839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10817104 + ... + 10817109.

It is an arithmetic number, because the mean of its divisors is an integer number (21634214).

Almost surely, 2^64902639 is an apocalyptic number.

64902639 is a deficient number, since it is larger than the sum of its proper divisors (21634217).

64902639 is a wasteful number, since it uses less digits than its factorization.

64902639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21634216.

The product of its (nonzero) digits is 69984, while the sum is 39.

The square root of 64902639 is about 8056.2174126571. The cubic root of 64902639 is about 401.8717258613.

The spelling of 64902639 in words is "sixty-four million, nine hundred two thousand, six hundred thirty-nine".