61691579 has 2 divisors, whose sum is σ = 61691580. Its totient is φ = 61691578.

The previous prime is 61691573. The next prime is 61691587. The reversal of 61691579 is 97519616.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61691579 is a prime.

It is not a weakly prime, because it can be changed into another prime (61691573) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30845789 + 30845790.

It is an arithmetic number, because the mean of its divisors is an integer number (30845790).

Almost surely, 2^61691579 is an apocalyptic number.

61691579 is a deficient number, since it is larger than the sum of its proper divisors (1).

61691579 is an equidigital number, since it uses as much as digits as its factorization.

61691579 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 102060, while the sum is 44.

The square root of 61691579 is about 7854.3987039111. The cubic root of 61691579 is about 395.1317810580.

The spelling of 61691579 in words is "sixty-one million, six hundred ninety-one thousand, five hundred seventy-nine".