66928275 has 72 divisors (see below), whose sum is σ = 129991680. Its totient is φ = 34071840.

The previous prime is 66928273. The next prime is 66928297. The reversal of 66928275 is 57282966.

It is not a de Polignac number, because 66928275 - 2¹ = 66928273 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 66928275.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66928271) 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, 139486 + ... + 139964.

It is an arithmetic number, because the mean of its divisors is an integer number (1805440).

Almost surely, 2^66928275 is an apocalyptic number.

66928275 is a deficient number, since it is larger than the sum of its proper divisors (63063405).

66928275 is a wasteful number, since it uses less digits than its factorization.

66928275 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 527 (or 510 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 66928275 is about 8180.9702969758. The cubic root of 66928275 is about 406.0098256902.

The spelling of 66928275 in words is "sixty-six million, nine hundred twenty-eight thousand, two hundred seventy-five".