64874781 has 12 divisors (see below), whose sum is σ = 95245020. Its totient is φ = 42540480.

The previous prime is 64874779. The next prime is 64874783. The reversal of 64874781 is 18747846.

It is an interprime number because it is at equal distance from previous prime (64874779) and next prime (64874783).

It can be written as a sum of positive squares in 2 ways, for example, as 17388900 + 47485881 = 4170^2 + 6891^2 .

It is not a de Polignac number, because 64874781 - 2¹ = 64874779 is a prime.

It is a super-2 number, since 2×64874781² = 8417474419595922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64874783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 58536 + ... + 59633.

It is an arithmetic number, because the mean of its divisors is an integer number (7937085).

Almost surely, 2^64874781 is an apocalyptic number.

64874781 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

64874781 is a deficient number, since it is larger than the sum of its proper divisors (30370239).

64874781 is a wasteful number, since it uses less digits than its factorization.

64874781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118236 (or 118233 counting only the distinct ones).

The product of its digits is 301056, while the sum is 45.

The square root of 64874781 is about 8054.4882519003. The cubic root of 64874781 is about 401.8142194955.

The spelling of 64874781 in words is "sixty-four million, eight hundred seventy-four thousand, seven hundred eighty-one".