64985531 has 4 divisors (see below), whose sum is σ = 69984432. Its totient is φ = 59986632.

The previous prime is 64985497. The next prime is 64985551. The reversal of 64985531 is 13558946.

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

It is a cyclic number.

It is not a de Polignac number, because 64985531 - 2⁶ = 64985467 is a prime.

It is a super-2 number, since 2×64985531² = 8446238478703922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64985551) 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, 2499431 + ... + 2499456.

It is an arithmetic number, because the mean of its divisors is an integer number (17496108).

Almost surely, 2^64985531 is an apocalyptic number.

64985531 is a deficient number, since it is larger than the sum of its proper divisors (4998901).

64985531 is a wasteful number, since it uses less digits than its factorization.

64985531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4998900.

The product of its digits is 129600, while the sum is 41.

The square root of 64985531 is about 8061.3603690692. The cubic root of 64985531 is about 402.0427398598.

The spelling of 64985531 in words is "sixty-four million, nine hundred eighty-five thousand, five hundred thirty-one".