61540279 has 2 divisors, whose sum is σ = 61540280. Its totient is φ = 61540278.

The previous prime is 61540247. The next prime is 61540309. The reversal of 61540279 is 97204516.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61540279 - 2⁵ = 61540247 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61544279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30770139 + 30770140.

It is an arithmetic number, because the mean of its divisors is an integer number (30770140).

Almost surely, 2^61540279 is an apocalyptic number.

61540279 is a deficient number, since it is larger than the sum of its proper divisors (1).

61540279 is an equidigital number, since it uses as much as digits as its factorization.

61540279 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 61540279 is about 7844.7612455702. The cubic root of 61540279 is about 394.8084933983.

The spelling of 61540279 in words is "sixty-one million, five hundred forty thousand, two hundred seventy-nine".