18997950 has 24 divisors (see below), whose sum is σ = 47115288. Its totient is φ = 5066080.

The previous prime is 18997919. The next prime is 18997969. The reversal of 18997950 is 5979981.

It is a self number, because there is not a number n which added to its sum of digits gives 18997950.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 63177 + ... + 63476.

It is an arithmetic number, because the mean of its divisors is an integer number (1963137).

Almost surely, 2^18997950 is an apocalyptic number.

18997950 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18997950 is an abundant number, since it is smaller than the sum of its proper divisors (28117338).

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

18997950 is a wasteful number, since it uses less digits than its factorization.

18997950 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126668 (or 126663 counting only the distinct ones).

The product of its (nonzero) digits is 204120, while the sum is 48.

The square root of 18997950 is about 4358.6637860702. The cubic root of 18997950 is about 266.8305676439.

The spelling of 18997950 in words is "eighteen million, nine hundred ninety-seven thousand, nine hundred fifty".