1959972661 has 2 divisors, whose sum is σ = 1959972662. Its totient is φ = 1959972660.

The previous prime is 1959972647. The next prime is 1959972713. The reversal of 1959972661 is 1662799591.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1470722500 + 489250161 = 38350^2 + 22119^2 .

It is a cyclic number.

It is not a de Polignac number, because 1959972661 - 2⁵ = 1959972629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1959972461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 979986330 + 979986331.

It is an arithmetic number, because the mean of its divisors is an integer number (979986331).

Almost surely, 2^1959972661 is an apocalyptic number.

It is an amenable number.

1959972661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1959972661 is an equidigital number, since it uses as much as digits as its factorization.

1959972661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1837080, while the sum is 55.

The square root of 1959972661 is about 44271.5784787486. The cubic root of 1959972661 is about 1251.4591304346.

The spelling of 1959972661 in words is "one billion, nine hundred fifty-nine million, nine hundred seventy-two thousand, six hundred sixty-one".