18201621240 has 128 divisors (see below), whose sum is σ = 66187756800. Its totient is φ = 4412511360.

The previous prime is 18201621227. The next prime is 18201621247. The reversal of 18201621240 is 4212610281.

18201621240 is a `hidden beast` number, since 18 + 2 + 0 + 1 + 621 + 24 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18201621247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 754182 + ... + 777941.

It is an arithmetic number, because the mean of its divisors is an integer number (517091850).

Almost surely, 2^18201621240 is an apocalyptic number.

18201621240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18201621240 is an abundant number, since it is smaller than the sum of its proper divisors (47986135560).

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

18201621240 is a wasteful number, since it uses less digits than its factorization.

18201621240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1532154 (or 1532144 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The spelling of 18201621240 in words is "eighteen billion, two hundred one million, six hundred twenty-one thousand, two hundred forty".