3900721318380 has 768 divisors, whose sum is σ = 13655900160000. Its totient is φ = 919819929600.

The previous prime is 3900721318369. The next prime is 3900721318397. The reversal of 3900721318380 is 838131270093.

It is a happy number.

3900721318380 is a `hidden beast` number, since 390 + 0 + 7 + 2 + 1 + 3 + 183 + 80 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 1659174205 + ... + 1659176555.

It is an arithmetic number, because the mean of its divisors is an integer number (17781120000).

Almost surely, 2^{3900721318380} is an apocalyptic number.

3900721318380 is a gapful number since it is divisible by the number (30) 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 3900721318380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6827950080000).

3900721318380 is an abundant number, since it is smaller than the sum of its proper divisors (9755178841620).

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

3900721318380 is a wasteful number, since it uses less digits than its factorization.

3900721318380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2579 (or 2571 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The spelling of 3900721318380 in words is "three trillion, nine hundred billion, seven hundred twenty-one million, three hundred eighteen thousand, three hundred eighty".