404020681 has 4 divisors (see below), whose sum is σ = 404674000. Its totient is φ = 403367364.

The previous prime is 404020651. The next prime is 404020699. The reversal of 404020681 is 186020404.

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 404020681 - 2¹³ = 404012489 is a prime.

It is a super-2 number, since 2×404020681² = 326465421351407522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (404020651) 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, 325731 + ... + 326968.

It is an arithmetic number, because the mean of its divisors is an integer number (101168500).

Almost surely, 2^404020681 is an apocalyptic number.

It is an amenable number.

404020681 is a deficient number, since it is larger than the sum of its proper divisors (653319).

404020681 is an equidigital number, since it uses as much as digits as its factorization.

404020681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 653318.

The product of its (nonzero) digits is 1536, while the sum is 25.

The square root of 404020681 is about 20100.2656947614. The cubic root of 404020681 is about 739.2667932430.

The spelling of 404020681 in words is "four hundred four million, twenty thousand, six hundred eighty-one".