61451320320 has 528 divisors, whose sum is σ = 231043088640. Its totient is φ = 15101558784.

The previous prime is 61451320303. The next prime is 61451320349. The reversal of 61451320320 is 2302315416.

61451320320 is a `hidden beast` number, since 6 + 1 + 451 + 3 + 203 + 2 + 0 = 666.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 101237457 + ... + 101238063.

Almost surely, 2^61451320320 is an apocalyptic number.

61451320320 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 61451320320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115521544320).

61451320320 is an abundant number, since it is smaller than the sum of its proper divisors (169591768320).

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

61451320320 is a wasteful number, since it uses less digits than its factorization.

61451320320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 677 (or 630 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

Adding to 61451320320 its reverse (2302315416), we get a palindrome (63753635736).

The spelling of 61451320320 in words is "sixty-one billion, four hundred fifty-one million, three hundred twenty thousand, three hundred twenty".