409390981 has 4 divisors (see below), whose sum is σ = 411842592. Its totient is φ = 406939372.

The previous prime is 409390973. The next prime is 409390997. The reversal of 409390981 is 189093904.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 409390981 - 2³ = 409390973 is a prime.

It is a super-2 number, since 2×409390981² = 335201950648284722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (409390901) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1225555 + ... + 1225888.

It is an arithmetic number, because the mean of its divisors is an integer number (102960648).

Almost surely, 2^409390981 is an apocalyptic number.

It is an amenable number.

409390981 is a deficient number, since it is larger than the sum of its proper divisors (2451611).

409390981 is a wasteful number, since it uses less digits than its factorization.

409390981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2451610.

The product of its (nonzero) digits is 69984, while the sum is 43.

The square root of 409390981 is about 20233.4124902351. The cubic root of 409390981 is about 742.5278663297.

The spelling of 409390981 in words is "four hundred nine million, three hundred ninety thousand, nine hundred eighty-one".