73727981 has 2 divisors, whose sum is σ = 73727982. Its totient is φ = 73727980.

The previous prime is 73727977. The next prime is 73728019. The reversal of 73727981 is 18972737.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 67798756 + 5929225 = 8234^2 + 2435^2 .

It is a cyclic number.

It is not a de Polignac number, because 73727981 - 2² = 73727977 is a prime.

It is a super-2 number, since 2×73727981² = 10871630364672722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (73727911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36863990 + 36863991.

It is an arithmetic number, because the mean of its divisors is an integer number (36863991).

Almost surely, 2^73727981 is an apocalyptic number.

It is an amenable number.

73727981 is a deficient number, since it is larger than the sum of its proper divisors (1).

73727981 is an equidigital number, since it uses as much as digits as its factorization.

73727981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 148176, while the sum is 44.

The square root of 73727981 is about 8586.4999272113. The cubic root of 73727981 is about 419.3185870534.

The spelling of 73727981 in words is "seventy-three million, seven hundred twenty-seven thousand, nine hundred eighty-one".