61444909 has 2 divisors, whose sum is σ = 61444910. Its totient is φ = 61444908.

The previous prime is 61444907. The next prime is 61444913. The reversal of 61444909 is 90944416.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 34633225 + 26811684 = 5885^2 + 5178^2 .

It is a cyclic number.

It is not a de Polignac number, because 61444909 - 2¹ = 61444907 is a prime.

Together with 61444907, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61444907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30722454 + 30722455.

It is an arithmetic number, because the mean of its divisors is an integer number (30722455).

Almost surely, 2^61444909 is an apocalyptic number.

It is an amenable number.

61444909 is a deficient number, since it is larger than the sum of its proper divisors (1).

61444909 is an equidigital number, since it uses as much as digits as its factorization.

61444909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 37.

The square root of 61444909 is about 7838.6803098481. The cubic root of 61444909 is about 394.6044408448.

The spelling of 61444909 in words is "sixty-one million, four hundred forty-four thousand, nine hundred nine".