1642955917 has 2 divisors, whose sum is σ = 1642955918. Its totient is φ = 1642955916.

The previous prime is 1642955819. The next prime is 1642955921. The reversal of 1642955917 is 7195592461.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1640979081 + 1976836 = 40509^2 + 1406^2 .

It is an emirp because it is prime and its reverse (7195592461) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1642955917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1642955927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 821477958 + 821477959.

It is an arithmetic number, because the mean of its divisors is an integer number (821477959).

Almost surely, 2^1642955917 is an apocalyptic number.

It is an amenable number.

1642955917 is a deficient number, since it is larger than the sum of its proper divisors (1).

1642955917 is an equidigital number, since it uses as much as digits as its factorization.

1642955917 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 680400, while the sum is 49.

The square root of 1642955917 is about 40533.3926164588. The cubic root of 1642955917 is about 1179.9817858435.

The spelling of 1642955917 in words is "one billion, six hundred forty-two million, nine hundred fifty-five thousand, nine hundred seventeen".