3991206929 has 2 divisors, whose sum is σ = 3991206930. Its totient is φ = 3991206928.

The previous prime is 3991206917. The next prime is 3991207009. The reversal of 3991206929 is 9296021993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2853696400 + 1137510529 = 53420^2 + 33727^2 .

It is a cyclic number.

It is not a de Polignac number, because 3991206929 - 2⁸ = 3991206673 is a prime.

It is a super-2 number, since 2×3991206929² = 31859465500195222082, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (3991203929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1995603464 + 1995603465.

It is an arithmetic number, because the mean of its divisors is an integer number (1995603465).

Almost surely, 2^3991206929 is an apocalyptic number.

It is an amenable number.

3991206929 is a deficient number, since it is larger than the sum of its proper divisors (1).

3991206929 is an equidigital number, since it uses as much as digits as its factorization.

3991206929 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 472392, while the sum is 50.

The square root of 3991206929 is about 63175.9996280233. Note that the first 3 decimals coincide. The cubic root of 3991206929 is about 1586.2370210876.

The spelling of 3991206929 in words is "three billion, nine hundred ninety-one million, two hundred six thousand, nine hundred twenty-nine".