61996309 has 2 divisors, whose sum is σ = 61996310. Its totient is φ = 61996308.

The previous prime is 61996307. The next prime is 61996327. The reversal of 61996309 is 90369916.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47196900 + 14799409 = 6870^2 + 3847^2 .

It is a cyclic number.

It is not a de Polignac number, because 61996309 - 2¹ = 61996307 is a prime.

Together with 61996307, 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 (61996303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30998154 + 30998155.

It is an arithmetic number, because the mean of its divisors is an integer number (30998155).

Almost surely, 2^61996309 is an apocalyptic number.

It is an amenable number.

61996309 is a deficient number, since it is larger than the sum of its proper divisors (1).

61996309 is an equidigital number, since it uses as much as digits as its factorization.

61996309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 78732, while the sum is 43.

The square root of 61996309 is about 7873.7734917891. The cubic root of 61996309 is about 395.7813067380.

The spelling of 61996309 in words is "sixty-one million, nine hundred ninety-six thousand, three hundred nine".