1622639 has 2 divisors, whose sum is σ = 1622640. Its totient is φ = 1622638.

The previous prime is 1622617. The next prime is 1622641. The reversal of 1622639 is 9362261.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1622639 - 2¹⁶ = 1557103 is a prime.

Together with 1622641, 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 (1622609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 811319 + 811320.

It is an arithmetic number, because the mean of its divisors is an integer number (811320).

2^1622639 is an apocalyptic number.

1622639 is a deficient number, since it is larger than the sum of its proper divisors (1).

1622639 is an equidigital number, since it uses as much as digits as its factorization.

1622639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3888, while the sum is 29.

The square root of 1622639 is about 1273.8284813899. The cubic root of 1622639 is about 117.5097683142.

The spelling of 1622639 in words is "one million, six hundred twenty-two thousand, six hundred thirty-nine".