61961917 has 4 divisors (see below), whose sum is σ = 61977916. Its totient is φ = 61945920.

The previous prime is 61961897. The next prime is 61961927. The reversal of 61961917 is 71916916.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 46049796 + 15912121 = 6786^2 + 3989^2 .

It is a cyclic number.

It is not a de Polignac number, because 61961917 - 2⁷ = 61961789 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 61961917.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61961927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1867 + ... + 11287.

It is an arithmetic number, because the mean of its divisors is an integer number (15494479).

Almost surely, 2^61961917 is an apocalyptic number.

It is an amenable number.

61961917 is a deficient number, since it is larger than the sum of its proper divisors (15999).

61961917 is an equidigital number, since it uses as much as digits as its factorization.

61961917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15998.

The product of its digits is 20412, while the sum is 40.

The square root of 61961917 is about 7871.5892296283. The cubic root of 61961917 is about 395.7081076036.

The spelling of 61961917 in words is "sixty-one million, nine hundred sixty-one thousand, nine hundred seventeen".