400428691 has 8 divisors (see below), whose sum is σ = 431756640. Its totient is φ = 369175872.

The previous prime is 400428641. The next prime is 400428697. The reversal of 400428691 is 196824004.

400428691 = 228² + 229² + ... + 1066².

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

It is not a de Polignac number, because 400428691 - 2⁷ = 400428563 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (400428697) 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, 7450 + ... + 29263.

It is an arithmetic number, because the mean of its divisors is an integer number (53969580).

Almost surely, 2^400428691 is an apocalyptic number.

400428691 is a deficient number, since it is larger than the sum of its proper divisors (31327949).

400428691 is a wasteful number, since it uses less digits than its factorization.

400428691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37565.

The product of its (nonzero) digits is 13824, while the sum is 34.

The square root of 400428691 is about 20010.7144050381. The cubic root of 400428691 is about 737.0694242757.

The spelling of 400428691 in words is "four hundred million, four hundred twenty-eight thousand, six hundred ninety-one".