61815005280 has 288 divisors, whose sum is σ = 251676240480. Its totient is φ = 14129095680.

The previous prime is 61815005257. The next prime is 61815005281. The reversal of 61815005280 is 8250051816.

61815005280 is a `hidden beast` number, since 6 + 1 + 81 + 50 + 0 + 528 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61815005281) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 65670 + ... + 357690.

It is an arithmetic number, because the mean of its divisors is an integer number (873875835).

Almost surely, 2^61815005280 is an apocalyptic number.

61815005280 is a gapful number since it is divisible by the number (60) 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 61815005280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125838120240).

61815005280 is an abundant number, since it is smaller than the sum of its proper divisors (189861235200).

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

61815005280 is a wasteful number, since it uses less digits than its factorization.

61815005280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 292059 (or 292038 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 36.

The spelling of 61815005280 in words is "sixty-one billion, eight hundred fifteen million, five thousand, two hundred eighty".