409945326921 has 24 divisors (see below), whose sum is σ = 637751898056. Its totient is φ = 252250640640.

The previous prime is 409945326913. The next prime is 409945326937. The reversal of 409945326921 is 129623549904.

409945326921 is a `hidden beast` number, since 40 + 9 + 9 + 4 + 532 + 69 + 2 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 43116446025 + 366828880896 = 207645^2 + 605664^2 .

It is not a de Polignac number, because 409945326921 - 2³ = 409945326913 is a prime.

It is not an unprimeable number, because it can be changed into a prime (409945326911) 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, 1148871 + ... + 1462803.

Almost surely, 2^409945326921 is an apocalyptic number.

It is an amenable number.

409945326921 is a deficient number, since it is larger than the sum of its proper divisors (227806571135).

409945326921 is a wasteful number, since it uses less digits than its factorization.

409945326921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 325113 (or 325110 counting only the distinct ones).

The product of its (nonzero) digits is 4199040, while the sum is 54.

The spelling of 409945326921 in words is "four hundred nine billion, nine hundred forty-five million, three hundred twenty-six thousand, nine hundred twenty-one".