401389809 has 4 divisors (see below), whose sum is σ = 535186416. Its totient is φ = 267593204.

The previous prime is 401389789. The next prime is 401389817. The reversal of 401389809 is 908983104.

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 401389809 - 2⁵ = 401389777 is a prime.

It is a super-2 number, since 2×401389809² = 322227557538112962, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (401389819) 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, 66898299 + ... + 66898304.

It is an arithmetic number, because the mean of its divisors is an integer number (133796604).

Almost surely, 2^401389809 is an apocalyptic number.

It is an amenable number.

401389809 is a deficient number, since it is larger than the sum of its proper divisors (133796607).

401389809 is a wasteful number, since it uses less digits than its factorization.

401389809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133796606.

The product of its (nonzero) digits is 62208, while the sum is 42.

The square root of 401389809 is about 20034.7150965518. The cubic root of 401389809 is about 737.6586633257.

The spelling of 401389809 in words is "four hundred one million, three hundred eighty-nine thousand, eight hundred nine".