1907981 has 2 divisors, whose sum is σ = 1907982. Its totient is φ = 1907980.

The previous prime is 1907963. The next prime is 1907987. The reversal of 1907981 is 1897091.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1865956 + 42025 = 1366^2 + 205^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1907981 is a prime.

It is a super-2 number, since 2×1907981² = 7280782992722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1907987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 953990 + 953991.

It is an arithmetic number, because the mean of its divisors is an integer number (953991).

2^1907981 is an apocalyptic number.

It is an amenable number.

1907981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1907981 is an equidigital number, since it uses as much as digits as its factorization.

1907981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4536, while the sum is 35.

The square root of 1907981 is about 1381.2968544089. The cubic root of 1907981 is about 124.0294111643.

The spelling of 1907981 in words is "one million, nine hundred seven thousand, nine hundred eighty-one".