81241738 has 4 divisors (see below), whose sum is σ = 121862610. Its totient is φ = 40620868.

The previous prime is 81241729. The next prime is 81241757. The reversal of 81241738 is 83714218.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 81234169 + 7569 = 9013^2 + 87^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20310433 + ... + 20310436.

Almost surely, 2^81241738 is an apocalyptic number.

81241738 is a deficient number, since it is larger than the sum of its proper divisors (40620872).

81241738 is a wasteful number, since it uses less digits than its factorization.

81241738 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40620871.

The product of its digits is 10752, while the sum is 34.

The square root of 81241738 is about 9013.4198837067. The cubic root of 81241738 is about 433.1048714190.

The spelling of 81241738 in words is "eighty-one million, two hundred forty-one thousand, seven hundred thirty-eight".