61638498 has 60 divisors (see below), whose sum is σ = 145357758. Its totient is φ = 18865920.

The previous prime is 61638497. The next prime is 61638529. The reversal of 61638498 is 89483616.

61638498 is a `hidden beast` number, since 6 + 1 + 638 + 4 + 9 + 8 = 666.

61638498 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 5 ways, for example, as 25674489 + 35964009 = 5067^2 + 5997^2 .

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (61638491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 1503358 + ... + 1503398.

Almost surely, 2^61638498 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61638498, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72678879).

61638498 is an abundant number, since it is smaller than the sum of its proper divisors (83719260).

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

61638498 is an equidigital number, since it uses as much as digits as its factorization.

61638498 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117 (or 63 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 61638498 is about 7851.0189147651. The cubic root of 61638498 is about 395.0184214023.

The spelling of 61638498 in words is "sixty-one million, six hundred thirty-eight thousand, four hundred ninety-eight".