84172990 has 16 divisors (see below), whose sum is σ = 165285360. Its totient is φ = 30608320.

The previous prime is 84172951. The next prime is 84172997. The reversal of 84172990 is 9927148.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84172997) by changing a digit.

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, 382495 + ... + 382714.

It is an arithmetic number, because the mean of its divisors is an integer number (10330335).

Almost surely, 2^84172990 is an apocalyptic number.

84172990 is a deficient number, since it is larger than the sum of its proper divisors (81112370).

84172990 is a wasteful number, since it uses less digits than its factorization.

84172990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 765227.

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 84172990 is about 9174.5839142710. The cubic root of 84172990 is about 438.2523479304.

The spelling of 84172990 in words is "eighty-four million, one hundred seventy-two thousand, nine hundred ninety".