61666380 has 48 divisors (see below), whose sum is σ = 191852640. Its totient is φ = 16444224.

The previous prime is 61666351. The next prime is 61666393. The reversal of 61666380 is 8366616.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56559 + ... + 57638.

It is an arithmetic number, because the mean of its divisors is an integer number (3996930).

Almost surely, 2^61666380 is an apocalyptic number.

61666380 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61666380 is an abundant number, since it is smaller than the sum of its proper divisors (130186260).

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

61666380 is a wasteful number, since it uses less digits than its factorization.

61666380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114215 (or 114207 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 61666380 is about 7852.7944070885. The cubic root of 61666380 is about 395.0779742450.

The spelling of 61666380 in words is "sixty-one million, six hundred sixty-six thousand, three hundred eighty".