61525868544 has 600 divisors, whose sum is σ = 216954239040. Its totient is φ = 17008164864.

The previous prime is 61525868531. The next prime is 61525868557. The reversal of 61525868544 is 44586852516.

61525868544 is a `hidden beast` number, since 6 + 1 + 5 + 2 + 586 + 8 + 54 + 4 = 666.

It is an interprime number because it is at equal distance from previous prime (61525868531) and next prime (61525868557).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 343719847 + ... + 343720025.

Almost surely, 2^61525868544 is an apocalyptic number.

61525868544 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61525868544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108477119520).

61525868544 is an abundant number, since it is smaller than the sum of its proper divisors (155428370496).

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

61525868544 is an equidigital number, since it uses as much as digits as its factorization.

61525868544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263 (or 228 counting only the distinct ones).

The product of its digits is 9216000, while the sum is 54.

The spelling of 61525868544 in words is "sixty-one billion, five hundred twenty-five million, eight hundred sixty-eight thousand, five hundred forty-four".