18361669491 has 32 divisors (see below), whose sum is σ = 29799705600. Its totient is φ = 11081679840.

The previous prime is 18361669481. The next prime is 18361669507. The reversal of 18361669491 is 19496616381.

It is a happy number.

18361669491 is a `hidden beast` number, since 1 + 83 + 6 + 16 + 69 + 491 = 666.

It is not a de Polignac number, because 18361669491 - 2⁷ = 18361669363 is a prime.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (18361669411) 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, 58356 + ... + 200321.

It is an arithmetic number, because the mean of its divisors is an integer number (931240800).

Almost surely, 2^18361669491 is an apocalyptic number.

18361669491 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

18361669491 is a deficient number, since it is larger than the sum of its proper divisors (11438036109).

18361669491 is a wasteful number, since it uses less digits than its factorization.

18361669491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258936 (or 258930 counting only the distinct ones).

The product of its digits is 1679616, while the sum is 54.

The spelling of 18361669491 in words is "eighteen billion, three hundred sixty-one million, six hundred sixty-nine thousand, four hundred ninety-one".