61879661 has 2 divisors, whose sum is σ = 61879662. Its totient is φ = 61879660.

The previous prime is 61879633. The next prime is 61879663. The reversal of 61879661 is 16697816.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46158436 + 15721225 = 6794^2 + 3965^2 .

It is a cyclic number.

It is not a de Polignac number, because 61879661 - 2¹⁰ = 61878637 is a prime.

It is a Sophie Germain prime.

Together with 61879663, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61879663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30939830 + 30939831.

It is an arithmetic number, because the mean of its divisors is an integer number (30939831).

Almost surely, 2^61879661 is an apocalyptic number.

It is an amenable number.

61879661 is a deficient number, since it is larger than the sum of its proper divisors (1).

61879661 is an equidigital number, since it uses as much as digits as its factorization.

61879661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108864, while the sum is 44.

The square root of 61879661 is about 7866.3626283054. The cubic root of 61879661 is about 395.5329259131.

The spelling of 61879661 in words is "sixty-one million, eight hundred seventy-nine thousand, six hundred sixty-one".