64536520 has 16 divisors (see below), whose sum is σ = 145207260. Its totient is φ = 25814592.

The previous prime is 64536509. The next prime is 64536523. The reversal of 64536520 is 2563546.

It can be written as a sum of positive squares in 2 ways, for example, as 63968004 + 568516 = 7998^2 + 754^2 .

It is not an unprimeable number, because it can be changed into a prime (64536523) 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, 806667 + ... + 806746.

Almost surely, 2^64536520 is an apocalyptic number.

It is an amenable number.

64536520 is an abundant number, since it is smaller than the sum of its proper divisors (80670740).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64536520 is a wasteful number, since it uses less digits than its factorization.

64536520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1613424 (or 1613420 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 31.

The square root of 64536520 is about 8033.4625162504. The cubic root of 64536520 is about 401.1146410532.

It can be divided in two parts, 64536 and 520, that added together give a palindrome (65056).

The spelling of 64536520 in words is "sixty-four million, five hundred thirty-six thousand, five hundred twenty".