18211954 has 12 divisors (see below), whose sum is σ = 28005642. Its totient is φ = 8882240.

The previous prime is 18211939. The next prime is 18211957. The reversal of 18211954 is 45911281.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 2331729 + 15880225 = 1527^2 + 3985^2 .

It is not an unprimeable number, because it can be changed into a prime (18211957) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 654 + ... + 6070.

Almost surely, 2^18211954 is an apocalyptic number.

18211954 is a deficient number, since it is larger than the sum of its proper divisors (9793688).

18211954 is an equidigital number, since it uses as much as digits as its factorization.

18211954 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5501 (or 5460 counting only the distinct ones).

The product of its digits is 2880, while the sum is 31.

The square root of 18211954 is about 4267.5466019717. The cubic root of 18211954 is about 263.0987884701.

The spelling of 18211954 in words is "eighteen million, two hundred eleven thousand, nine hundred fifty-four".