61665100247 has 16 divisors (see below), whose sum is σ = 64044512352. Its totient is φ = 59324803200.

The previous prime is 61665100181. The next prime is 61665100253. The reversal of 61665100247 is 74200156616.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61665100247 is a prime.

It is a super-2 number, since 2×61665100247² (a number of 22 digits) contains 22 as substring.

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 61665100247.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61665100447) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2878028 + ... + 2899374.

It is an arithmetic number, because the mean of its divisors is an integer number (4002782022).

Almost surely, 2^61665100247 is an apocalyptic number.

61665100247 is a deficient number, since it is larger than the sum of its proper divisors (2379412105).

61665100247 is a wasteful number, since it uses less digits than its factorization.

61665100247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22258.

The product of its (nonzero) digits is 60480, while the sum is 38.

The spelling of 61665100247 in words is "sixty-one billion, six hundred sixty-five million, one hundred thousand, two hundred forty-seven".