18390938617456 has 20 divisors (see below), whose sum is σ = 35754056015832. Its totient is φ = 9164085452096.

The previous prime is 18390938617439. The next prime is 18390938617523. The reversal of 18390938617456 is 65471683909381.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1961486206 + ... + 1961495581.

Almost surely, 2^{18390938617456} is an apocalyptic number.

18390938617456 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

18390938617456 is a deficient number, since it is larger than the sum of its proper divisors (17363117398376).

18390938617456 is a wasteful number, since it uses less digits than its factorization.

18390938617456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3922982088 (or 3922982082 counting only the distinct ones).

The product of its (nonzero) digits is 235146240, while the sum is 70.

The spelling of 18390938617456 in words is "eighteen trillion, three hundred ninety billion, nine hundred thirty-eight million, six hundred seventeen thousand, four hundred fifty-six".