667921090 has 8 divisors (see below), whose sum is σ = 1202257980. Its totient is φ = 267168432.

The previous prime is 667921073. The next prime is 667921103. The reversal of 667921090 is 90129766.

It can be written as a sum of positive squares in 2 ways, for example, as 599809081 + 68112009 = 24491^2 + 8253^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×667921090² = 892237164933576200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33396045 + ... + 33396064.

Almost surely, 2^667921090 is an apocalyptic number.

667921090 is a deficient number, since it is larger than the sum of its proper divisors (534336890).

667921090 is a wasteful number, since it uses less digits than its factorization.

667921090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66792116.

The product of its (nonzero) digits is 40824, while the sum is 40.

The square root of 667921090 is about 25844.1693617729. The cubic root of 667921090 is about 874.1280412926.

The spelling of 667921090 in words is "six hundred sixty-seven million, nine hundred twenty-one thousand, ninety".