18531378480 has 40 divisors (see below), whose sum is σ = 57447274032. Its totient is φ = 4941700864.

The previous prime is 18531378473. The next prime is 18531378487. The reversal of 18531378480 is 8487313581.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (18531378473) and next prime (18531378487).

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×18531378480² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (18531378487) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 38606799 + ... + 38607278.

Almost surely, 2^18531378480 is an apocalyptic number.

18531378480 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18531378480 is an abundant number, since it is smaller than the sum of its proper divisors (38915895552).

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

18531378480 is a wasteful number, since it uses less digits than its factorization.

18531378480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77214093 (or 77214087 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 48.

The spelling of 18531378480 in words is "eighteen billion, five hundred thirty-one million, three hundred seventy-eight thousand, four hundred eighty".