400161637 has 2 divisors, whose sum is σ = 400161638. Its totient is φ = 400161636.

The previous prime is 400161583. The next prime is 400161649. The reversal of 400161637 is 736161004.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 356416641 + 43744996 = 18879^2 + 6614^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-400161637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400161667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200080818 + 200080819.

It is an arithmetic number, because the mean of its divisors is an integer number (200080819).

Almost surely, 2^400161637 is an apocalyptic number.

It is an amenable number.

400161637 is a deficient number, since it is larger than the sum of its proper divisors (1).

400161637 is an equidigital number, since it uses as much as digits as its factorization.

400161637 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 400161637 is about 20004.0405168556. The cubic root of 400161637 is about 736.9055323295.

The spelling of 400161637 in words is "four hundred million, one hundred sixty-one thousand, six hundred thirty-seven".