81121752 has 48 divisors (see below), whose sum is σ = 220311000. Its totient is φ = 26966016.

The previous prime is 81121751. The next prime is 81121757. The reversal of 81121752 is 25712118.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81121751) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 28824 + ... + 31512.

Almost surely, 2^81121752 is an apocalyptic number.

It is an amenable number.

81121752 is an abundant number, since it is smaller than the sum of its proper divisors (139189248).

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

81121752 is a wasteful number, since it uses less digits than its factorization.

81121752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3120 (or 3113 counting only the distinct ones).

The product of its digits is 1120, while the sum is 27.

The square root of 81121752 is about 9006.7614601476. The cubic root of 81121752 is about 432.8915487004.

The spelling of 81121752 in words is "eighty-one million, one hundred twenty-one thousand, seven hundred fifty-two".