18990477 has 32 divisors (see below), whose sum is σ = 31426560. Its totient is φ = 11234160.

The previous prime is 18990469. The next prime is 18990487. The reversal of 18990477 is 77409981.

It is not a de Polignac number, because 18990477 - 2³ = 18990469 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18990427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12028 + ... + 13514.

It is an arithmetic number, because the mean of its divisors is an integer number (982080).

Almost surely, 2^18990477 is an apocalyptic number.

It is an amenable number.

18990477 is a deficient number, since it is larger than the sum of its proper divisors (12436083).

18990477 is a wasteful number, since it uses less digits than its factorization.

18990477 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1550 (or 1544 counting only the distinct ones).

The product of its (nonzero) digits is 127008, while the sum is 45.

The square root of 18990477 is about 4357.8064436136. The cubic root of 18990477 is about 266.7955763888.

It can be divided in two parts, 189904 and 77, that added together give a palindrome (189981).

The spelling of 18990477 in words is "eighteen million, nine hundred ninety thousand, four hundred seventy-seven".