61899699816 has 96 divisors (see below), whose sum is σ = 173908425600. Its totient is φ = 19875098880.

The previous prime is 61899699793. The next prime is 61899699847.

61899699816 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 100495 + ... + 365921.

It is an arithmetic number, because the mean of its divisors is an integer number (1811546100).

Almost surely, 2^61899699816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61899699816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86954212800).

61899699816 is an abundant number, since it is smaller than the sum of its proper divisors (112008725784).

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

61899699816 is a wasteful number, since it uses less digits than its factorization.

61899699816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265559 (or 265552 counting only the distinct ones).

The product of its digits is 90699264, while the sum is 72.

The spelling of 61899699816 in words is "sixty-one billion, eight hundred ninety-nine million, six hundred ninety-nine thousand, eight hundred sixteen".