3705408978921 has 24 divisors (see below), whose sum is σ = 5780580449280. Its totient is φ = 2273680323936.

The previous prime is 3705408978883. The next prime is 3705408978941. The reversal of 3705408978921 is 1298798045073.

3705408978921 is a `hidden beast` number, since 3 + 7 + 0 + 540 + 8 + 9 + 7 + 89 + 2 + 1 = 666.

It is not a de Polignac number, because 3705408978921 - 2⁹ = 3705408978409 is a prime.

It is not an unprimeable number, because it can be changed into a prime (3705408978941) 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, 45593641 + ... + 45674838.

It is an arithmetic number, because the mean of its divisors is an integer number (240857518720).

Almost surely, 2^{3705408978921} is an apocalyptic number.

It is an amenable number.

3705408978921 is a deficient number, since it is larger than the sum of its proper divisors (2075171470359).

3705408978921 is a wasteful number, since it uses less digits than its factorization.

3705408978921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91268845 (or 91268842 counting only the distinct ones).

The product of its (nonzero) digits is 30481920, while the sum is 63.

The spelling of 3705408978921 in words is "three trillion, seven hundred five billion, four hundred eight million, nine hundred seventy-eight thousand, nine hundred twenty-one".