61515550940 has 192 divisors, whose sum is σ = 142053004800. Its totient is φ = 22290038784.

The previous prime is 61515550939. The next prime is 61515550949. The reversal of 61515550940 is 4905551516.

61515550940 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61515550949) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 268626746 + ... + 268626974.

It is an arithmetic number, because the mean of its divisors is an integer number (739859400).

Almost surely, 2^61515550940 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 61515550940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71026502400).

61515550940 is an abundant number, since it is smaller than the sum of its proper divisors (80537453860).

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

61515550940 is a wasteful number, since it uses less digits than its factorization.

61515550940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 544 (or 542 counting only the distinct ones).

The product of its (nonzero) digits is 135000, while the sum is 41.

The spelling of 61515550940 in words is "sixty-one billion, five hundred fifteen million, five hundred fifty thousand, nine hundred forty".