1622261621 has 2 divisors, whose sum is σ = 1622261622. Its totient is φ = 1622261620.

The previous prime is 1622261609. The next prime is 1622261623. The reversal of 1622261621 is 1261622261.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1265580625 + 356680996 = 35575^2 + 18886^2 .

It is a cyclic number.

It is not a de Polignac number, because 1622261621 - 2²² = 1618067317 is a prime.

Together with 1622261623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1622261623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 811130810 + 811130811.

It is an arithmetic number, because the mean of its divisors is an integer number (811130811).

Almost surely, 2^1622261621 is an apocalyptic number.

It is an amenable number.

1622261621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1622261621 is an equidigital number, since it uses as much as digits as its factorization.

1622261621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 29.

The square root of 1622261621 is about 40277.3090089197. The cubic root of 1622261621 is about 1175.0065781433.

Adding to 1622261621 its reverse (1261622261), we get a palindrome (2883883882).

The spelling of 1622261621 in words is "one billion, six hundred twenty-two million, two hundred sixty-one thousand, six hundred twenty-one".