64673973 has 72 divisors (see below), whose sum is σ = 121375800. Its totient is φ = 32852736.

The previous prime is 64673963. The next prime is 64673977. The reversal of 64673973 is 37937646.

It can be written as a sum of positive squares in 4 ways, for example, as 321489 + 64352484 = 567^2 + 8022^2 .

It is not a de Polignac number, because 64673973 - 2⁴ = 64673957 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

Its product of digits (571536) is a multiple of the sum of its prime divisors (441).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64673977) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 166063 + ... + 166451.

It is an arithmetic number, because the mean of its divisors is an integer number (1685775).

Almost surely, 2^64673973 is an apocalyptic number.

64673973 is a gapful number since it is divisible by the number (63) formed by its first and last digit.

It is an amenable number.

64673973 is a deficient number, since it is larger than the sum of its proper divisors (56701827).

64673973 is a wasteful number, since it uses less digits than its factorization.

64673973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 451 (or 441 counting only the distinct ones).

The product of its digits is 571536, while the sum is 45.

The square root of 64673973 is about 8042.0129942695. The cubic root of 64673973 is about 401.3992102365.

It can be divided in two parts, 6467 and 3973, that added together give a triangular number (10440 = T₁₄₄).

The spelling of 64673973 in words is "sixty-four million, six hundred seventy-three thousand, nine hundred seventy-three".