1431891649 has 2 divisors, whose sum is σ = 1431891650. Its totient is φ = 1431891648.

The previous prime is 1431891641. The next prime is 1431891673. The reversal of 1431891649 is 9461981341.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 726033025 + 705858624 = 26945^2 + 26568^2 .

It is a cyclic number.

It is not a de Polignac number, because 1431891649 - 2³ = 1431891641 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1431891599 and 1431891608.

It is not a weakly prime, because it can be changed into another prime (1431891641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 715945824 + 715945825.

It is an arithmetic number, because the mean of its divisors is an integer number (715945825).

Almost surely, 2^1431891649 is an apocalyptic number.

It is an amenable number.

1431891649 is a deficient number, since it is larger than the sum of its proper divisors (1).

1431891649 is an equidigital number, since it uses as much as digits as its factorization.

1431891649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 186624, while the sum is 46.

The square root of 1431891649 is about 37840.3441976946. The cubic root of 1431891649 is about 1127.1197299725.

The spelling of 1431891649 in words is "one billion, four hundred thirty-one million, eight hundred ninety-one thousand, six hundred forty-nine".