81616052 has 24 divisors (see below), whose sum is σ = 170330496. Its totient is φ = 33457248.

The previous prime is 81616049. The next prime is 81616061. The reversal of 81616052 is 25061618.

It is a happy number.

It is a super-2 number, since 2×81616052² = 13322359888133408, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62723 + ... + 64010.

It is an arithmetic number, because the mean of its divisors is an integer number (7097104).

Almost surely, 2^81616052 is an apocalyptic number.

It is an amenable number.

81616052 is an abundant number, since it is smaller than the sum of its proper divisors (88714444).

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

81616052 is a wasteful number, since it uses less digits than its factorization.

81616052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126767 (or 126765 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 81616052 is about 9034.1602819521. The cubic root of 81616052 is about 433.7690163771.

The spelling of 81616052 in words is "eighty-one million, six hundred sixteen thousand, fifty-two".