400191649 has 12 divisors (see below), whose sum is σ = 473718868. Its totient is φ = 335823840.

The previous prime is 400191641. The next prime is 400191653. The reversal of 400191649 is 946191004.

It can be written as a sum of positive squares in 2 ways, for example, as 85377600 + 314814049 = 9240^2 + 17743^2 .

It is not a de Polignac number, because 400191649 - 2³ = 400191641 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 (400191641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 125634 + ... + 128779.

Almost surely, 2^400191649 is an apocalyptic number.

It is an amenable number.

400191649 is a deficient number, since it is larger than the sum of its proper divisors (73527219).

400191649 is a wasteful number, since it uses less digits than its factorization.

400191649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254448 (or 254437 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 400191649 is about 20004.7906512415. The cubic root of 400191649 is about 736.9239544319.

The spelling of 400191649 in words is "four hundred million, one hundred ninety-one thousand, six hundred forty-nine".