64874021 has 4 divisors (see below), whose sum is σ = 65347692. Its totient is φ = 64400352.

The previous prime is 64874011. The next prime is 64874027. The reversal of 64874021 is 12047846.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12047846 = 2 ⋅6023923.

It can be written as a sum of positive squares in 2 ways, for example, as 15100996 + 49773025 = 3886^2 + 7055^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64874021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64874027) 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, 236630 + ... + 236903.

It is an arithmetic number, because the mean of its divisors is an integer number (16336923).

Almost surely, 2^64874021 is an apocalyptic number.

It is an amenable number.

64874021 is a deficient number, since it is larger than the sum of its proper divisors (473671).

64874021 is a wasteful number, since it uses less digits than its factorization.

64874021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 473670.

The product of its (nonzero) digits is 10752, while the sum is 32.

The square root of 64874021 is about 8054.4410730975. The cubic root of 64874021 is about 401.8126504215.

The spelling of 64874021 in words is "sixty-four million, eight hundred seventy-four thousand, twenty-one".