64920481 has 4 divisors (see below), whose sum is σ = 64948500. Its totient is φ = 64892464.

The previous prime is 64920463. The next prime is 64920491. The reversal of 64920481 is 18402946.

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

It can be written as a sum of positive squares in 2 ways, for example, as 56010256 + 8910225 = 7484^2 + 2985^2 .

It is a cyclic number.

It is not a de Polignac number, because 64920481 - 2⁷ = 64920353 is a prime.

It is a super-2 number, since 2×64920481² = 8429337706542722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64920491) 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, 10186 + ... + 15283.

It is an arithmetic number, because the mean of its divisors is an integer number (16237125).

Almost surely, 2^64920481 is an apocalyptic number.

It is an amenable number.

64920481 is a deficient number, since it is larger than the sum of its proper divisors (28019).

64920481 is a wasteful number, since it uses less digits than its factorization.

64920481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28018.

The product of its (nonzero) digits is 13824, while the sum is 34.

The square root of 64920481 is about 8057.3246800660. The cubic root of 64920481 is about 401.9085478792.

The spelling of 64920481 in words is "sixty-four million, nine hundred twenty thousand, four hundred eighty-one".