18949940 has 24 divisors (see below), whose sum is σ = 40185600. Its totient is φ = 7505568.

The previous prime is 18949877. The next prime is 18949949. The reversal of 18949940 is 4994981.

It is a junction number, because it is equal to n+sod(n) for n = 18949891 and 18949900.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18949949) 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, 2540 + ... + 6659.

It is an arithmetic number, because the mean of its divisors is an integer number (1674400).

Almost surely, 2^18949940 is an apocalyptic number.

18949940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18949940 is an abundant number, since it is smaller than the sum of its proper divisors (21235660).

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

18949940 is a wasteful number, since it uses less digits than its factorization.

18949940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9311 (or 9309 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 44.

The square root of 18949940 is about 4353.1528803845. The cubic root of 18949940 is about 266.6056075480.

The spelling of 18949940 in words is "eighteen million, nine hundred forty-nine thousand, nine hundred forty".