181490437 has 2 divisors, whose sum is σ = 181490438. Its totient is φ = 181490436.

The previous prime is 181490377. The next prime is 181490467. The reversal of 181490437 is 734094181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 180472356 + 1018081 = 13434^2 + 1009^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-181490437 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 181490396 and 181490405.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (181490467) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90745218 + 90745219.

It is an arithmetic number, because the mean of its divisors is an integer number (90745219).

Almost surely, 2^181490437 is an apocalyptic number.

It is an amenable number.

181490437 is a deficient number, since it is larger than the sum of its proper divisors (1).

181490437 is an equidigital number, since it uses as much as digits as its factorization.

181490437 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 181490437 is about 13471.8386644140. The cubic root of 181490437 is about 566.1757300821.

The spelling of 181490437 in words is "one hundred eighty-one million, four hundred ninety thousand, four hundred thirty-seven".