18139722 has 16 divisors (see below), whose sum is σ = 37123680. Its totient is φ = 5905872.

The previous prime is 18139711. The next prime is 18139729. The reversal of 18139722 is 22793181.

It is not an unprimeable number, because it can be changed into a prime (18139729) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34897 + ... + 35412.

It is an arithmetic number, because the mean of its divisors is an integer number (2320230).

Almost surely, 2^18139722 is an apocalyptic number.

18139722 is an abundant number, since it is smaller than the sum of its proper divisors (18983958).

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

18139722 is a wasteful number, since it uses less digits than its factorization.

18139722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70357.

The product of its digits is 6048, while the sum is 33.

The square root of 18139722 is about 4259.0752517419. The cubic root of 18139722 is about 262.7504946724.

It can be divided in two parts, 181 and 39722, that added together give a triangular number (39903 = T₂₈₂).

The spelling of 18139722 in words is "eighteen million, one hundred thirty-nine thousand, seven hundred twenty-two".