61516818 has 48 divisors (see below), whose sum is σ = 146948256. Its totient is φ = 18443520.

The previous prime is 61516811. The next prime is 61516831. The reversal of 61516818 is 81861516.

61516818 is a `hidden beast` number, since 61 + 516 + 81 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (61516811) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17605 + ... + 20807.

It is an arithmetic number, because the mean of its divisors is an integer number (3061422).

Almost surely, 2^61516818 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61516818, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73474128).

61516818 is an abundant number, since it is smaller than the sum of its proper divisors (85431438).

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

61516818 is a wasteful number, since it uses less digits than its factorization.

61516818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3319 (or 3316 counting only the distinct ones).

The product of its digits is 11520, while the sum is 36.

The square root of 61516818 is about 7843.2657738980. The cubic root of 61516818 is about 394.7583160753.

The spelling of 61516818 in words is "sixty-one million, five hundred sixteen thousand, eight hundred eighteen".