81249037 has 2 divisors, whose sum is σ = 81249038. Its totient is φ = 81249036.

The previous prime is 81249019. The next prime is 81249067. The reversal of 81249037 is 73094218.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47073321 + 34175716 = 6861^2 + 5846^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81249037 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81248993 and 81249011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81249067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40624518 + 40624519.

It is an arithmetic number, because the mean of its divisors is an integer number (40624519).

Almost surely, 2^81249037 is an apocalyptic number.

It is an amenable number.

81249037 is a deficient number, since it is larger than the sum of its proper divisors (1).

81249037 is an equidigital number, since it uses as much as digits as its factorization.

81249037 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 81249037 is about 9013.8247708728. The cubic root of 81249037 is about 433.1178415083.

It can be divided in two parts, 8124 and 9037, that added together give a square (17161 = 131²).

The spelling of 81249037 in words is "eighty-one million, two hundred forty-nine thousand, thirty-seven".