861402977 has 2 divisors, whose sum is σ = 861402978. Its totient is φ = 861402976.

The previous prime is 861402973. The next prime is 861403007. The reversal of 861402977 is 779204168.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 763472161 + 97930816 = 27631^2 + 9896^2 .

It is a cyclic number.

It is not a de Polignac number, because 861402977 - 2² = 861402973 is a prime.

It is not a weakly prime, because it can be changed into another prime (861402973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430701488 + 430701489.

It is an arithmetic number, because the mean of its divisors is an integer number (430701489).

Almost surely, 2^861402977 is an apocalyptic number.

It is an amenable number.

861402977 is a deficient number, since it is larger than the sum of its proper divisors (1).

861402977 is an equidigital number, since it uses as much as digits as its factorization.

861402977 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 169344, while the sum is 44.

The square root of 861402977 is about 29349.6674086777. The cubic root of 861402977 is about 951.4853870931.

The spelling of 861402977 in words is "eight hundred sixty-one million, four hundred two thousand, nine hundred seventy-seven".