1631045261 has 2 divisors, whose sum is σ = 1631045262. Its totient is φ = 1631045260.

The previous prime is 1631045249. The next prime is 1631045279. The reversal of 1631045261 is 1625401361.

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., 893651236 + 737394025 = 29894^2 + 27155^2 .

It is a cyclic number.

It is not a de Polignac number, because 1631045261 - 2¹⁰ = 1631044237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1631045461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 815522630 + 815522631.

It is an arithmetic number, because the mean of its divisors is an integer number (815522631).

Almost surely, 2^1631045261 is an apocalyptic number.

It is an amenable number.

1631045261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1631045261 is an equidigital number, since it uses as much as digits as its factorization.

1631045261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 1631045261 is about 40386.2013687844. The cubic root of 1631045261 is about 1177.1234301751.

The spelling of 1631045261 in words is "one billion, six hundred thirty-one million, forty-five thousand, two hundred sixty-one".