1631402609 has 2 divisors, whose sum is σ = 1631402610. Its totient is φ = 1631402608.

The previous prime is 1631402579. The next prime is 1631402657. The reversal of 1631402609 is 9062041361.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1162810000 + 468592609 = 34100^2 + 21647^2 .

It is a cyclic number.

It is not a de Polignac number, because 1631402609 - 2¹² = 1631398513 is a prime.

It is a super-2 number, since 2×1631402609² = 5322948945304013762, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1631402009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 815701304 + 815701305.

It is an arithmetic number, because the mean of its divisors is an integer number (815701305).

Almost surely, 2^1631402609 is an apocalyptic number.

It is an amenable number.

1631402609 is a deficient number, since it is larger than the sum of its proper divisors (1).

1631402609 is an equidigital number, since it uses as much as digits as its factorization.

1631402609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 1631402609 is about 40390.6252613153. The cubic root of 1631402609 is about 1177.2093897737.

The spelling of 1631402609 in words is "one billion, six hundred thirty-one million, four hundred two thousand, six hundred nine".