18501949 has 4 divisors (see below), whose sum is σ = 18511164. Its totient is φ = 18492736.

The previous prime is 18501937. The next prime is 18502013. The reversal of 18501949 is 94910581.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 12376324 + 6125625 = 3518^2 + 2475^2 .

It is a cyclic number.

It is not a de Polignac number, because 18501949 - 2¹³ = 18493757 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18501149) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 172 + ... + 6085.

It is an arithmetic number, because the mean of its divisors is an integer number (4627791).

Almost surely, 2^18501949 is an apocalyptic number.

It is an amenable number.

18501949 is a deficient number, since it is larger than the sum of its proper divisors (9215).

18501949 is an equidigital number, since it uses as much as digits as its factorization.

18501949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9214.

The product of its (nonzero) digits is 12960, while the sum is 37.

The square root of 18501949 is about 4301.3891942023. The cubic root of 18501949 is about 264.4879110354.

The spelling of 18501949 in words is "eighteen million, five hundred one thousand, nine hundred forty-nine".