1631426389 has 2 divisors, whose sum is σ = 1631426390. Its totient is φ = 1631426388.

The previous prime is 1631426339. The next prime is 1631426441. The reversal of 1631426389 is 9836241361.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1282857489 + 348568900 = 35817^2 + 18670^2 .

It is a cyclic number.

It is not a de Polignac number, because 1631426389 - 2²¹ = 1629329237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1631426339) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 815713194 + 815713195.

It is an arithmetic number, because the mean of its divisors is an integer number (815713195).

Almost surely, 2^1631426389 is an apocalyptic number.

It is an amenable number.

1631426389 is a deficient number, since it is larger than the sum of its proper divisors (1).

1631426389 is an equidigital number, since it uses as much as digits as its factorization.

1631426389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 186624, while the sum is 43.

The square root of 1631426389 is about 40390.9196354824. The cubic root of 1631426389 is about 1177.2151095764.

The spelling of 1631426389 in words is "one billion, six hundred thirty-one million, four hundred twenty-six thousand, three hundred eighty-nine".