6662721385440 has 96 divisors (see below), whose sum is σ = 23319524864160. Its totient is φ = 1776725701632.

The previous prime is 6662721385433. The next prime is 6662721385451. The reversal of 6662721385440 is 445831272666.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 771143989 + ... + 771152628.

It is an arithmetic number, because the mean of its divisors is an integer number (242911717335).

Almost surely, 2^{6662721385440} is an apocalyptic number.

6662721385440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6662721385440 is an abundant number, since it is smaller than the sum of its proper divisors (16656803478720).

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

6662721385440 is a wasteful number, since it uses less digits than its factorization.

6662721385440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1542296641 (or 1542296627 counting only the distinct ones).

The product of its (nonzero) digits is 11612160, while the sum is 54.

The spelling of 6662721385440 in words is "six trillion, six hundred sixty-two billion, seven hundred twenty-one million, three hundred eighty-five thousand, four hundred forty".