1642215557 has 2 divisors, whose sum is σ = 1642215558. Its totient is φ = 1642215556.

The previous prime is 1642215551. The next prime is 1642215559. The reversal of 1642215557 is 7555122461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1575613636 + 66601921 = 39694^2 + 8161^2 .

It is a cyclic number.

It is not a de Polignac number, because 1642215557 - 2⁴ = 1642215541 is a prime.

Together with 1642215559, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1642215557.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1642215551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 821107778 + 821107779.

It is an arithmetic number, because the mean of its divisors is an integer number (821107779).

Almost surely, 2^1642215557 is an apocalyptic number.

It is an amenable number.

1642215557 is a deficient number, since it is larger than the sum of its proper divisors (1).

1642215557 is an equidigital number, since it uses as much as digits as its factorization.

1642215557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 84000, while the sum is 38.

The square root of 1642215557 is about 40524.2588704593. The cubic root of 1642215557 is about 1179.8045154001.

The spelling of 1642215557 in words is "one billion, six hundred forty-two million, two hundred fifteen thousand, five hundred fifty-seven".