61855933955815 has 8 divisors (see below), whose sum is σ = 74228288093280. Its totient is φ = 49483968933792.

The previous prime is 61855933955801. The next prime is 61855933955839. The reversal of 61855933955815 is 51855933955816.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61855933955815 is a prime.

It is a super-2 number, since 2×61855933955815² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 96929020 + ... + 97565089.

It is an arithmetic number, because the mean of its divisors is an integer number (9278536011660).

Almost surely, 2^{61855933955815} is an apocalyptic number.

61855933955815 is a deficient number, since it is larger than the sum of its proper divisors (12372354137465).

61855933955815 is a wasteful number, since it uses less digits than its factorization.

61855933955815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194557721.

The product of its digits is 874800000, while the sum is 73.

Subtracting from 61855933955815 its reverse (51855933955816), we obtain a palindrome (9999999999999).

The spelling of 61855933955815 in words is "sixty-one trillion, eight hundred fifty-five billion, nine hundred thirty-three million, nine hundred fifty-five thousand, eight hundred fifteen".