72166690 has 16 divisors (see below), whose sum is σ = 130003128. Its totient is φ = 28843776.

The previous prime is 72166673. The next prime is 72166711. The reversal of 72166690 is 9666127.

It can be written as a sum of positive squares in 4 ways, for example, as 59613841 + 12552849 = 7721^2 + 3543^2 .

It is a super-2 number, since 2×72166690² = 10416062291112200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16804 + ... + 20656.

Almost surely, 2^72166690 is an apocalyptic number.

72166690 is a deficient number, since it is larger than the sum of its proper divisors (57836438).

72166690 is a wasteful number, since it uses less digits than its factorization.

72166690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5733.

The product of its (nonzero) digits is 27216, while the sum is 37.

The square root of 72166690 is about 8495.0979982576. The cubic root of 72166690 is about 416.3375627036.

The spelling of 72166690 in words is "seventy-two million, one hundred sixty-six thousand, six hundred ninety".