1431131561 has 2 divisors, whose sum is σ = 1431131562. Its totient is φ = 1431131560.

The previous prime is 1431131557. The next prime is 1431131677. The reversal of 1431131561 is 1651311341.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 826217536 + 604914025 = 28744^2 + 24595^2 .

It is a cyclic number.

It is not a de Polignac number, because 1431131561 - 2² = 1431131557 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1431131561.

It is not a weakly prime, because it can be changed into another prime (1431131521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 715565780 + 715565781.

It is an arithmetic number, because the mean of its divisors is an integer number (715565781).

Almost surely, 2^1431131561 is an apocalyptic number.

It is an amenable number.

1431131561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1431131561 is an equidigital number, since it uses as much as digits as its factorization.

1431131561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1080, while the sum is 26.

The square root of 1431131561 is about 37830.2995097845. The cubic root of 1431131561 is about 1126.9202591501.

The spelling of 1431131561 in words is "one billion, four hundred thirty-one million, one hundred thirty-one thousand, five hundred sixty-one".