66920780 has 12 divisors (see below), whose sum is σ = 140533680. Its totient is φ = 26768304.

The previous prime is 66920767. The next prime is 66920797. The reversal of 66920780 is 8702966.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1673000 + ... + 1673039.

It is an arithmetic number, because the mean of its divisors is an integer number (11711140).

Almost surely, 2^66920780 is an apocalyptic number.

It is an amenable number.

66920780 is an abundant number, since it is smaller than the sum of its proper divisors (73612900).

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

66920780 is a wasteful number, since it uses less digits than its factorization.

66920780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3346048 (or 3346046 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 38.

The square root of 66920780 is about 8180.5122089023. The cubic root of 66920780 is about 405.9946693792.

The spelling of 66920780 in words is "sixty-six million, nine hundred twenty thousand, seven hundred eighty".