347791981 has 2 divisors, whose sum is σ = 347791982. Its totient is φ = 347791980.

The previous prime is 347791973. The next prime is 347791991. The reversal of 347791981 is 189197743.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 308529225 + 39262756 = 17565^2 + 6266^2 .

It is a cyclic number.

It is not a de Polignac number, because 347791981 - 2³ = 347791973 is a prime.

It is a super-2 number, since 2×347791981² = 241918524095808722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (347791931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 173895990 + 173895991.

It is an arithmetic number, because the mean of its divisors is an integer number (173895991).

Almost surely, 2^347791981 is an apocalyptic number.

It is an amenable number.

347791981 is a deficient number, since it is larger than the sum of its proper divisors (1).

347791981 is an equidigital number, since it uses as much as digits as its factorization.

347791981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 381024, while the sum is 49.

The square root of 347791981 is about 18649.1817782979. The cubic root of 347791981 is about 703.2447868633.

The spelling of 347791981 in words is "three hundred forty-seven million, seven hundred ninety-one thousand, nine hundred eighty-one".