18949433264640 has 240 divisors, whose sum is σ = 65634361917696. Its totient is φ = 5052632064000.

The previous prime is 18949433264639. The next prime is 18949433264647. The reversal of 18949433264640 is 4646233494981.

18949433264640 is a `hidden beast` number, since 1 + 89 + 4 + 9 + 433 + 2 + 64 + 64 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is not an unprimeable number, because it can be changed into a prime (18949433264647) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 239369065 + ... + 239448215.

Almost surely, 2^{18949433264640} is an apocalyptic number.

18949433264640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18949433264640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32817180958848).

18949433264640 is an abundant number, since it is smaller than the sum of its proper divisors (46684928653056).

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

18949433264640 is a wasteful number, since it uses less digits than its factorization.

18949433264640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89571 (or 89552 counting only the distinct ones).

The product of its (nonzero) digits is 107495424, while the sum is 63.

The spelling of 18949433264640 in words is "eighteen trillion, nine hundred forty-nine billion, four hundred thirty-three million, two hundred sixty-four thousand, six hundred forty".