61811527680 has 520 divisors, whose sum is σ = 253280398272. Its totient is φ = 14125694976.

The previous prime is 61811527639. The next prime is 61811527691. The reversal of 61811527680 is 8672511816.

61811527680 is a `hidden beast` number, since 61 + 8 + 1 + 1 + 527 + 68 + 0 = 666.

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

It is a nialpdrome in base 16.

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, 11609499 + ... + 11614821.

Almost surely, 2^61811527680 is an apocalyptic number.

61811527680 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 61811527680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (126640199136).

61811527680 is an abundant number, since it is smaller than the sum of its proper divisors (191468870592).

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

61811527680 is an equidigital number, since it uses as much as digits as its factorization.

61811527680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5371 (or 5340 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 45.

The spelling of 61811527680 in words is "sixty-one billion, eight hundred eleven million, five hundred twenty-seven thousand, six hundred eighty".