61641215999 has 8 divisors (see below), whose sum is σ = 68055144192. Its totient is φ = 55362318040.

The previous prime is 61641215981. The next prime is 61641216023. The reversal of 61641215999 is 99951214616.

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

It is not a de Polignac number, because 61641215999 - 2²⁸ = 61372780543 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 61641215999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61641215939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33756599 + ... + 33758424.

It is an arithmetic number, because the mean of its divisors is an integer number (8506893024).

Almost surely, 2^61641215999 is an apocalyptic number.

61641215999 is a deficient number, since it is larger than the sum of its proper divisors (6413928193).

61641215999 is a wasteful number, since it uses less digits than its factorization.

61641215999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67515117.

The product of its digits is 1049760, while the sum is 53.

The spelling of 61641215999 in words is "sixty-one billion, six hundred forty-one million, two hundred fifteen thousand, nine hundred ninety-nine".