61783979 has 2 divisors, whose sum is σ = 61783980. Its totient is φ = 61783978.

The previous prime is 61783951. The next prime is 61783999. The reversal of 61783979 is 97938716.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61783979 - 2⁸ = 61783723 is a prime.

It is a super-2 number, since 2×61783979² = 7634520122144882, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (61783999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30891989 + 30891990.

It is an arithmetic number, because the mean of its divisors is an integer number (30891990).

Almost surely, 2^61783979 is an apocalyptic number.

61783979 is a deficient number, since it is larger than the sum of its proper divisors (1).

61783979 is an equidigital number, since it uses as much as digits as its factorization.

61783979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 571536, while the sum is 50.

The square root of 61783979 is about 7860.2785574049. The cubic root of 61783979 is about 395.3289552608.

The spelling of 61783979 in words is "sixty-one million, seven hundred eighty-three thousand, nine hundred seventy-nine".