61866120 has 64 divisors (see below), whose sum is σ = 186984000. Its totient is φ = 16374528.

The previous prime is 61866107. The next prime is 61866131. The reversal of 61866120 is 2166816.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14826 + ... + 18534.

It is an arithmetic number, because the mean of its divisors is an integer number (2921625).

Almost surely, 2^61866120 is an apocalyptic number.

61866120 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61866120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93492000).

61866120 is an abundant number, since it is smaller than the sum of its proper divisors (125117880).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61866120 is a wasteful number, since it uses less digits than its factorization.

61866120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3862 (or 3858 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 61866120 is about 7865.5018911701. The cubic root of 61866120 is about 395.5040725872.

The spelling of 61866120 in words is "sixty-one million, eight hundred sixty-six thousand, one hundred twenty".