400570661 has 4 divisors (see below), whose sum is σ = 408128652. Its totient is φ = 393012672.

The previous prime is 400570631. The next prime is 400570717. The reversal of 400570661 is 166075004.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 298944100 + 101626561 = 17290^2 + 10081^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-400570661 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400570631) 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, 3778916 + ... + 3779021.

It is an arithmetic number, because the mean of its divisors is an integer number (102032163).

Almost surely, 2^400570661 is an apocalyptic number.

It is an amenable number.

400570661 is a deficient number, since it is larger than the sum of its proper divisors (7557991).

400570661 is an equidigital number, since it uses as much as digits as its factorization.

400570661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7557990.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 400570661 is about 20014.2614402830. The cubic root of 400570661 is about 737.1565220821.

The spelling of 400570661 in words is "four hundred million, five hundred seventy thousand, six hundred sixty-one".