81742970880 has 600 divisors, whose sum is σ = 298407234048. Its totient is φ = 21403533312.

The previous prime is 81742970873. The next prime is 81742970921. The reversal of 81742970880 is 8807924718.

It is a happy number.

It is a super-3 number, since 3×81742970880³ (a number of 34 digits) contains 333 as substring.

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, 643645377 + ... + 643645503.

Almost surely, 2^81742970880 is an apocalyptic number.

81742970880 is a gapful number since it is divisible by the number (80) 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 81742970880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (149203617024).

81742970880 is an abundant number, since it is smaller than the sum of its proper divisors (216664263168).

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

81742970880 is an equidigital number, since it uses as much as digits as its factorization.

81742970880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269 (or 234 counting only the distinct ones).

The product of its (nonzero) digits is 1806336, while the sum is 54.

The spelling of 81742970880 in words is "eighty-one billion, seven hundred forty-two million, nine hundred seventy thousand, eight hundred eighty".