39349721 has 2 divisors, whose sum is σ = 39349722. Its totient is φ = 39349720.

The previous prime is 39349693. The next prime is 39349733. The reversal of 39349721 is 12794393.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 32775625 + 6574096 = 5725^2 + 2564^2 .

It is an emirp because it is prime and its reverse (12794393) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 39349721 - 2⁶ = 39349657 is a prime.

It is not a weakly prime, because it can be changed into another prime (39349621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19674860 + 19674861.

It is an arithmetic number, because the mean of its divisors is an integer number (19674861).

Almost surely, 2^39349721 is an apocalyptic number.

It is an amenable number.

39349721 is a deficient number, since it is larger than the sum of its proper divisors (1).

39349721 is an equidigital number, since it uses as much as digits as its factorization.

39349721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40824, while the sum is 38.

The square root of 39349721 is about 6272.9355966724. The cubic root of 39349721 is about 340.1317857061.

The spelling of 39349721 in words is "thirty-nine million, three hundred forty-nine thousand, seven hundred twenty-one".