18940999 has 12 divisors (see below), whose sum is σ = 24037128. Its totient is φ = 14758800.

The previous prime is 18940993. The next prime is 18941011. The reversal of 18940999 is 99904981.

It is not a de Polignac number, because 18940999 - 2³ = 18940991 is a prime.

It is a super-2 number, since 2×18940999² = 717522886236002, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18940991) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17032 + ... + 18109.

It is an arithmetic number, because the mean of its divisors is an integer number (2003094).

Almost surely, 2^18940999 is an apocalyptic number.

18940999 is a deficient number, since it is larger than the sum of its proper divisors (5096129).

18940999 is a wasteful number, since it uses less digits than its factorization.

18940999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35166 (or 35159 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 49.

The square root of 18940999 is about 4352.1258024097. The cubic root of 18940999 is about 266.5636708149.

The spelling of 18940999 in words is "eighteen million, nine hundred forty thousand, nine hundred ninety-nine".