1962664721 has 2 divisors, whose sum is σ = 1962664722. Its totient is φ = 1962664720.

The previous prime is 1962664657. The next prime is 1962664723. The reversal of 1962664721 is 1274662691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1515934225 + 446730496 = 38935^2 + 21136^2 .

It is a cyclic number.

It is not a de Polignac number, because 1962664721 - 2⁶ = 1962664657 is a prime.

Together with 1962664723, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1962664723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 981332360 + 981332361.

It is an arithmetic number, because the mean of its divisors is an integer number (981332361).

Almost surely, 2^1962664721 is an apocalyptic number.

It is an amenable number.

1962664721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1962664721 is an equidigital number, since it uses as much as digits as its factorization.

1962664721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 44.

The square root of 1962664721 is about 44301.9719764256. The cubic root of 1962664721 is about 1252.0318360045.

The spelling of 1962664721 in words is "one billion, nine hundred sixty-two million, six hundred sixty-four thousand, seven hundred twenty-one".