81372373 has 2 divisors, whose sum is σ = 81372374. Its totient is φ = 81372372.

The previous prime is 81372349. The next prime is 81372397. The reversal of 81372373 is 37327318.

It is a balanced prime because it is at equal distance from previous prime (81372349) and next prime (81372397).

It can be written as a sum of positive squares in only one way, i.e., 67519089 + 13853284 = 8217^2 + 3722^2 .

It is a cyclic number.

It is not a de Polignac number, because 81372373 - 2¹⁷ = 81241301 is a prime.

It is a super-2 number, since 2×81372373² = 13242926175302258, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81372073) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40686186 + 40686187.

It is an arithmetic number, because the mean of its divisors is an integer number (40686187).

Almost surely, 2^81372373 is an apocalyptic number.

It is an amenable number.

81372373 is a deficient number, since it is larger than the sum of its proper divisors (1).

81372373 is an equidigital number, since it uses as much as digits as its factorization.

81372373 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21168, while the sum is 34.

The square root of 81372373 is about 9020.6636673806. The cubic root of 81372373 is about 433.3368882680.

The spelling of 81372373 in words is "eighty-one million, three hundred seventy-two thousand, three hundred seventy-three".