81212152 has 32 divisors (see below), whose sum is σ = 175212000. Its totient is φ = 34568064.

The previous prime is 81212147. The next prime is 81212161. The reversal of 81212152 is 25121218.

It is a super-2 number, since 2×81212152² = 13190827264942208, 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, 3478 + ... + 13210.

It is an arithmetic number, because the mean of its divisors is an integer number (5475375).

Almost surely, 2^81212152 is an apocalyptic number.

It is an amenable number.

81212152 is an abundant number, since it is smaller than the sum of its proper divisors (93999848).

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

81212152 is a wasteful number, since it uses less digits than its factorization.

81212152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9895 (or 9891 counting only the distinct ones).

The product of its digits is 320, while the sum is 22.

The square root of 81212152 is about 9011.7785148105. The cubic root of 81212152 is about 433.0522900865.

The spelling of 81212152 in words is "eighty-one million, two hundred twelve thousand, one hundred fifty-two".