30981749 has 2 divisors, whose sum is σ = 30981750. Its totient is φ = 30981748.

The previous prime is 30981737. The next prime is 30981757. The reversal of 30981749 is 94718903.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22972849 + 8008900 = 4793^2 + 2830^2 .

It is a cyclic number.

It is not a de Polignac number, because 30981749 - 2¹⁶ = 30916213 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30981149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15490874 + 15490875.

It is an arithmetic number, because the mean of its divisors is an integer number (15490875).

Almost surely, 2^30981749 is an apocalyptic number.

It is an amenable number.

30981749 is a deficient number, since it is larger than the sum of its proper divisors (1).

30981749 is an equidigital number, since it uses as much as digits as its factorization.

30981749 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54432, while the sum is 41.

The square root of 30981749 is about 5566.1251333401. The cubic root of 30981749 is about 314.0764043859.

The spelling of 30981749 in words is "thirty million, nine hundred eighty-one thousand, seven hundred forty-nine".