66769920 has 440 divisors, whose sum is σ = 285335424. Its totient is φ = 14598144.

The previous prime is 66769909. The next prime is 66769949. The reversal of 66769920 is 2996766.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 2903029 + ... + 2903051.

Almost surely, 2^66769920 is an apocalyptic number.

66769920 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66769920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142667712).

66769920 is an abundant number, since it is smaller than the sum of its proper divisors (218565504).

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

66769920 is a wasteful number, since it uses less digits than its factorization.

66769920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67 (or 40 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 45.

The square root of 66769920 is about 8171.2863124480. The cubic root of 66769920 is about 405.6893609347.

The spelling of 66769920 in words is "sixty-six million, seven hundred sixty-nine thousand, nine hundred twenty".