81148730 has 24 divisors (see below), whose sum is σ = 158171292. Its totient is φ = 29961984.

The previous prime is 81148709. The next prime is 81148741. The reversal of 81148730 is 3784118.

It can be written as a sum of positive squares in 6 ways, for example, as 1635841 + 79512889 = 1279^2 + 8917^2 .

It is a super-2 number, since 2×81148730² = 13170232761225800, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22319 + ... + 25698.

Almost surely, 2^81148730 is an apocalyptic number.

81148730 is a deficient number, since it is larger than the sum of its proper divisors (77022562).

81148730 is a wasteful number, since it uses less digits than its factorization.

81148730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48050 (or 48037 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 32.

The square root of 81148730 is about 9008.2589882840. The cubic root of 81148730 is about 432.9395311200.

The spelling of 81148730 in words is "eighty-one million, one hundred forty-eight thousand, seven hundred thirty".