104139781 has 2 divisors, whose sum is σ = 104139782. Its totient is φ = 104139780.

The previous prime is 104139767. The next prime is 104139821. The reversal of 104139781 is 187931401.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54154881 + 49984900 = 7359^2 + 7070^2 .

It is a cyclic number.

It is not a de Polignac number, because 104139781 - 2²⁵ = 70585349 is a prime.

It is a super-2 number, since 2×104139781² = 21690187973455922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (104139731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 52069890 + 52069891.

It is an arithmetic number, because the mean of its divisors is an integer number (52069891).

Almost surely, 2^104139781 is an apocalyptic number.

It is an amenable number.

104139781 is a deficient number, since it is larger than the sum of its proper divisors (1).

104139781 is an equidigital number, since it uses as much as digits as its factorization.

104139781 is an evil number, because the sum of its binary digits is even.

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

The square root of 104139781 is about 10204.8900533029. The cubic root of 104139781 is about 470.4775303477.

The spelling of 104139781 in words is "one hundred four million, one hundred thirty-nine thousand, seven hundred eighty-one".