30739721 has 2 divisors, whose sum is σ = 30739722. Its totient is φ = 30739720.

The previous prime is 30739699. The next prime is 30739747. The reversal of 30739721 is 12793703.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24364096 + 6375625 = 4936^2 + 2525^2 .

It is a cyclic number.

It is not a de Polignac number, because 30739721 - 2²² = 26545417 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is equal to p_1900949 and since 30739721 and 1900949 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (30739771) 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, 15369860 + 15369861.

It is an arithmetic number, because the mean of its divisors is an integer number (15369861).

Almost surely, 2^30739721 is an apocalyptic number.

It is an amenable number.

30739721 is a deficient number, since it is larger than the sum of its proper divisors (1).

30739721 is an equidigital number, since it uses as much as digits as its factorization.

30739721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7938, while the sum is 32.

The square root of 30739721 is about 5544.3413495202. The cubic root of 30739721 is about 313.2564152777.

The spelling of 30739721 in words is "thirty million, seven hundred thirty-nine thousand, seven hundred twenty-one".