66990371 has 16 divisors (see below), whose sum is σ = 81404160. Its totient is φ = 53848800.

The previous prime is 66990337. The next prime is 66990373. The reversal of 66990371 is 17309966.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 66990371 - 2⁶ = 66990307 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66990373) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10940 + ... + 15926.

It is an arithmetic number, because the mean of its divisors is an integer number (5087760).

Almost surely, 2^66990371 is an apocalyptic number.

66990371 is a deficient number, since it is larger than the sum of its proper divisors (14413789).

66990371 is a wasteful number, since it uses less digits than its factorization.

66990371 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5114.

The product of its (nonzero) digits is 61236, while the sum is 41.

The square root of 66990371 is about 8184.7645659481. The cubic root of 66990371 is about 406.1353520743.

The spelling of 66990371 in words is "sixty-six million, nine hundred ninety thousand, three hundred seventy-one".