61979409 has 24 divisors (see below), whose sum is σ = 93910440. Its totient is φ = 39336192.

The previous prime is 61979389. The next prime is 61979453. The reversal of 61979409 is 90497916.

It can be written as a sum of positive squares in 4 ways, for example, as 31674384 + 30305025 = 5628^2 + 5505^2 .

It is not a de Polignac number, because 61979409 - 2⁵ = 61979377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (61979459) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17427 + ... + 20679.

It is an arithmetic number, because the mean of its divisors is an integer number (3912935).

Almost surely, 2^61979409 is an apocalyptic number.

It is an amenable number.

61979409 is a deficient number, since it is larger than the sum of its proper divisors (31931031).

61979409 is a wasteful number, since it uses less digits than its factorization.

61979409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3361 (or 3358 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 45.

The square root of 61979409 is about 7872.7002356244. The cubic root of 61979409 is about 395.7453405541.

The spelling of 61979409 in words is "sixty-one million, nine hundred seventy-nine thousand, four hundred nine".