81863332 has 6 divisors (see below), whose sum is σ = 143260838. Its totient is φ = 40931664.

The previous prime is 81863329. The next prime is 81863333. The reversal of 81863332 is 23336818.

It can be written as a sum of positive squares in only one way, i.e., 80748196 + 1115136 = 8986^2 + 1056^2 .

It is a super-2 number, since 2×81863332² = 13403210252284448, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81863333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10232913 + ... + 10232920.

Almost surely, 2^81863332 is an apocalyptic number.

It is an amenable number.

81863332 is a deficient number, since it is larger than the sum of its proper divisors (61397506).

81863332 is a wasteful number, since it uses less digits than its factorization.

81863332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20465837 (or 20465835 counting only the distinct ones).

The product of its digits is 20736, while the sum is 34.

The square root of 81863332 is about 9047.8357633193. The cubic root of 81863332 is about 434.2066519237.

The spelling of 81863332 in words is "eighty-one million, eight hundred sixty-three thousand, three hundred thirty-two".