400042221977 has 2 divisors, whose sum is σ = 400042221978. Its totient is φ = 400042221976.

The previous prime is 400042221959. The next prime is 400042222057. The reversal of 400042221977 is 779122240004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 312083118736 + 87959103241 = 558644^2 + 296579^2 .

It is a cyclic number.

It is not a de Polignac number, because 400042221977 - 2²² = 400038027673 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 400042221977.

It is not a weakly prime, because it can be changed into another prime (400042121977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200021110988 + 200021110989.

It is an arithmetic number, because the mean of its divisors is an integer number (200021110989).

Almost surely, 2^400042221977 is an apocalyptic number.

It is an amenable number.

400042221977 is a deficient number, since it is larger than the sum of its proper divisors (1).

400042221977 is an equidigital number, since it uses as much as digits as its factorization.

400042221977 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 56448, while the sum is 38.

The spelling of 400042221977 in words is "four hundred billion, forty-two million, two hundred twenty-one thousand, nine hundred seventy-seven".