29978909 has 2 divisors, whose sum is σ = 29978910. Its totient is φ = 29978908.

The previous prime is 29978899. The next prime is 29978911. The reversal of 29978909 is 90987992.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28408900 + 1570009 = 5330^2 + 1253^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-29978909 is a prime.

Together with 29978911, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (29978609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14989454 + 14989455.

It is an arithmetic number, because the mean of its divisors is an integer number (14989455).

Almost surely, 2^29978909 is an apocalyptic number.

It is an amenable number.

29978909 is a deficient number, since it is larger than the sum of its proper divisors (1).

29978909 is an equidigital number, since it uses as much as digits as its factorization.

29978909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 734832, while the sum is 53.

The square root of 29978909 is about 5475.2999004621. The cubic root of 29978909 is about 310.6504172571.

The spelling of 29978909 in words is "twenty-nine million, nine hundred seventy-eight thousand, nine hundred nine".