61961986 has 4 divisors (see below), whose sum is σ = 92942982. Its totient is φ = 30980992.

The previous prime is 61961981. The next prime is 61961989. The reversal of 61961986 is 68916916.

61961986 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 37271025 + 24690961 = 6105^2 + 4969^2 .

It is not an unprimeable number, because it can be changed into a prime (61961981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15490495 + ... + 15490498.

Almost surely, 2^61961986 is an apocalyptic number.

61961986 is a deficient number, since it is larger than the sum of its proper divisors (30980996).

61961986 is a wasteful number, since it uses less digits than its factorization.

61961986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30980995.

The product of its digits is 139968, while the sum is 46.

The square root of 61961986 is about 7871.5936124777. The cubic root of 61961986 is about 395.7082544887.

The spelling of 61961986 in words is "sixty-one million, nine hundred sixty-one thousand, nine hundred eighty-six".