61198640 has 60 divisors (see below), whose sum is σ = 151206096. Its totient is φ = 23030784.

The previous prime is 61198603. The next prime is 61198649. The reversal of 61198640 is 4689116.

It is a self number, because there is not a number n which added to its sum of digits gives 61198640.

It is not an unprimeable number, because it can be changed into a prime (61198649) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21797 + ... + 24443.

Almost surely, 2^61198640 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 61198640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75603048).

61198640 is an abundant number, since it is smaller than the sum of its proper divisors (90007456).

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

61198640 is a wasteful number, since it uses less digits than its factorization.

61198640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2694 (or 2671 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 61198640 is about 7822.9559630615. The cubic root of 61198640 is about 394.0765481235.

The spelling of 61198640 in words is "sixty-one million, one hundred ninety-eight thousand, six hundred forty".