61731217 has 2 divisors, whose sum is σ = 61731218. Its totient is φ = 61731216.

The previous prime is 61731211. The next prime is 61731221. The reversal of 61731217 is 71213716.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57168721 + 4562496 = 7561^2 + 2136^2 .

It is a cyclic number.

It is not a de Polignac number, because 61731217 - 2¹¹ = 61729169 is a prime.

It is not a weakly prime, because it can be changed into another prime (61731211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30865608 + 30865609.

It is an arithmetic number, because the mean of its divisors is an integer number (30865609).

Almost surely, 2^61731217 is an apocalyptic number.

It is an amenable number.

61731217 is a deficient number, since it is larger than the sum of its proper divisors (1).

61731217 is an equidigital number, since it uses as much as digits as its factorization.

61731217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1764, while the sum is 28.

The square root of 61731217 is about 7856.9215981833. The cubic root of 61731217 is about 395.2163894738.

The spelling of 61731217 in words is "sixty-one million, seven hundred thirty-one thousand, two hundred seventeen".