140931781 has 2 divisors, whose sum is σ = 140931782. Its totient is φ = 140931780.

The previous prime is 140931761. The next prime is 140931809. The reversal of 140931781 is 187139041.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 140209281 + 722500 = 11841^2 + 850^2 .

It is a cyclic number.

It is not a de Polignac number, because 140931781 - 2¹⁵ = 140899013 is a prime.

It is a super-2 number, since 2×140931781² = 39723533791663922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (140931701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 70465890 + 70465891.

It is an arithmetic number, because the mean of its divisors is an integer number (70465891).

Almost surely, 2^140931781 is an apocalyptic number.

It is an amenable number.

140931781 is a deficient number, since it is larger than the sum of its proper divisors (1).

140931781 is an equidigital number, since it uses as much as digits as its factorization.

140931781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6048, while the sum is 34.

The square root of 140931781 is about 11871.4692014089. The cubic root of 140931781 is about 520.3988323369.

The spelling of 140931781 in words is "one hundred forty million, nine hundred thirty-one thousand, seven hundred eighty-one".