61009865280 has 1344 divisors, whose sum is σ = 274161991680. Its totient is φ = 12499329024.

The previous prime is 61009865269. The next prime is 61009865333. The reversal of 61009865280 is 8256890016.

61009865280 is a `hidden beast` number, since 610 + 0 + 9 + 8 + 6 + 5 + 28 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a super-2 number, since 2×61009865280² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 480392577 + ... + 480392703.

Almost surely, 2^61009865280 is an apocalyptic number.

61009865280 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 61009865280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137080995840).

61009865280 is an abundant number, since it is smaller than the sum of its proper divisors (213152126400).

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

61009865280 is a wasteful number, since it uses less digits than its factorization.

61009865280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233 (or 204 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The spelling of 61009865280 in words is "sixty-one billion, nine million, eight hundred sixty-five thousand, two hundred eighty".