400052557661 has 2 divisors, whose sum is σ = 400052557662. Its totient is φ = 400052557660.

The previous prime is 400052557643. The next prime is 400052557703. The reversal of 400052557661 is 166755250004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 394076340025 + 5976217636 = 627755^2 + 77306^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-400052557661 is a prime.

It is a super-2 number, since 2×400052557661² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400052557621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200026278830 + 200026278831.

It is an arithmetic number, because the mean of its divisors is an integer number (200026278831).

Almost surely, 2^400052557661 is an apocalyptic number.

It is an amenable number.

400052557661 is a deficient number, since it is larger than the sum of its proper divisors (1).

400052557661 is an equidigital number, since it uses as much as digits as its factorization.

400052557661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 252000, while the sum is 41.

The spelling of 400052557661 in words is "four hundred billion, fifty-two million, five hundred fifty-seven thousand, six hundred sixty-one".