400400691 has 8 divisors (see below), whose sum is σ = 534078720. Its totient is φ = 266828232.

The previous prime is 400400687. The next prime is 400400701. The reversal of 400400691 is 196004004.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 400400691 - 2² = 400400687 is a prime.

It is not an unprimeable number, because it can be changed into a prime (400400591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17071 + ... + 33048.

It is an arithmetic number, because the mean of its divisors is an integer number (66759840).

Almost surely, 2^400400691 is an apocalyptic number.

400400691 is a deficient number, since it is larger than the sum of its proper divisors (133678029).

400400691 is a wasteful number, since it uses less digits than its factorization.

400400691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52785.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 400400691 is about 20010.0147676107. The cubic root of 400400691 is about 737.0522440008.

Adding to 400400691 its reverse (196004004), we get a palindrome (596404695).

The spelling of 400400691 in words is "four hundred million, four hundred thousand, six hundred ninety-one".