18901521477 has 32 divisors (see below), whose sum is σ = 28628968320. Its totient is φ = 12476106000.

The previous prime is 18901521467. The next prime is 18901521511. The reversal of 18901521477 is 77412510981.

It is a happy number.

18901521477 is a `hidden beast` number, since 1 + 89 + 0 + 1 + 521 + 47 + 7 = 666.

It is not a de Polignac number, because 18901521477 - 2¹² = 18901517381 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18901521437) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 178102 + ... + 263672.

It is an arithmetic number, because the mean of its divisors is an integer number (894655260).

Almost surely, 2^18901521477 is an apocalyptic number.

It is an amenable number.

18901521477 is a deficient number, since it is larger than the sum of its proper divisors (9727446843).

18901521477 is an frugal number, since it uses more digits than its factorization.

18901521477 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85693 (or 85675 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 45.

The spelling of 18901521477 in words is "eighteen billion, nine hundred one million, five hundred twenty-one thousand, four hundred seventy-seven".