66994920 has 48 divisors (see below), whose sum is σ = 217734660. Its totient is φ = 17865216.

The previous prime is 66994891. The next prime is 66994927. The reversal of 66994920 is 2949966.

It can be written as a sum of positive squares in 2 ways, for example, as 66683556 + 311364 = 8166^2 + 558^2 .

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

It is not an unprimeable number, because it can be changed into a prime (66994927) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 92689 + ... + 93408.

Almost surely, 2^66994920 is an apocalyptic number.

66994920 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66994920 is an abundant number, since it is smaller than the sum of its proper divisors (150739740).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66994920 is a wasteful number, since it uses less digits than its factorization.

66994920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186114 (or 186107 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 45.

The square root of 66994920 is about 8185.0424556016. The cubic root of 66994920 is about 406.1445447780.

The spelling of 66994920 in words is "sixty-six million, nine hundred ninety-four thousand, nine hundred twenty".