81948730 has 32 divisors (see below), whose sum is σ = 152077824. Its totient is φ = 31777536.

The previous prime is 81948677. The next prime is 81948731. The reversal of 81948730 is 3784918.

It is a super-2 number, since 2×81948730² = 13431188697225800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81948731) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 52339 + ... + 53881.

It is an arithmetic number, because the mean of its divisors is an integer number (4752432).

Almost surely, 2^81948730 is an apocalyptic number.

81948730 is a deficient number, since it is larger than the sum of its proper divisors (70129094).

81948730 is a wasteful number, since it uses less digits than its factorization.

81948730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1710.

The product of its (nonzero) digits is 48384, while the sum is 40.

The square root of 81948730 is about 9052.5537833255. The cubic root of 81948730 is about 434.3575843474.

The spelling of 81948730 in words is "eighty-one million, nine hundred forty-eight thousand, seven hundred thirty".