61211866 has 16 divisors (see below), whose sum is σ = 100572840. Its totient is φ = 27811840.

The previous prime is 61211861. The next prime is 61211867. The reversal of 61211866 is 66811216.

It can be written as a sum of positive squares in 4 ways, for example, as 45171841 + 16040025 = 6721^2 + 4005^2 .

It is not an unprimeable number, because it can be changed into a prime (61211861) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30055 + ... + 32026.

Almost surely, 2^61211866 is an apocalyptic number.

61211866 is a deficient number, since it is larger than the sum of its proper divisors (39360974).

61211866 is a wasteful number, since it uses less digits than its factorization.

61211866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62129.

The product of its digits is 3456, while the sum is 31.

The square root of 61211866 is about 7823.8012500319. The cubic root of 61211866 is about 394.1049348164.

The spelling of 61211866 in words is "sixty-one million, two hundred eleven thousand, eight hundred sixty-six".