61665997 has 8 divisors (see below), whose sum is σ = 62663744. Its totient is φ = 60676128.

The previous prime is 61665991. The next prime is 61666019. The reversal of 61665997 is 79956616.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 61665997 - 2⁷ = 61665869 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 61665997.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61665991) 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, 14953 + ... + 18625.

It is an arithmetic number, because the mean of its divisors is an integer number (7832968).

Almost surely, 2^61665997 is an apocalyptic number.

It is an amenable number.

61665997 is a deficient number, since it is larger than the sum of its proper divisors (997747).

61665997 is a wasteful number, since it uses less digits than its factorization.

61665997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3939.

The product of its digits is 612360, while the sum is 49.

The square root of 61665997 is about 7852.7700208270. The cubic root of 61665997 is about 395.0771563214.

The spelling of 61665997 in words is "sixty-one million, six hundred sixty-five thousand, nine hundred ninety-seven".