81490852 has 6 divisors (see below), whose sum is σ = 142608998. Its totient is φ = 40745424.

The previous prime is 81490837. The next prime is 81490853. The reversal of 81490852 is 25809418.

It can be written as a sum of positive squares in only one way, i.e., 75759616 + 5731236 = 8704^2 + 2394^2 .

It is not an unprimeable number, because it can be changed into a prime (81490853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10186353 + ... + 10186360.

Almost surely, 2^81490852 is an apocalyptic number.

It is an amenable number.

81490852 is a deficient number, since it is larger than the sum of its proper divisors (61118146).

81490852 is a wasteful number, since it uses less digits than its factorization.

81490852 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20372717 (or 20372715 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 37.

The square root of 81490852 is about 9027.2283675556. The cubic root of 81490852 is about 433.5471005780.

The spelling of 81490852 in words is "eighty-one million, four hundred ninety thousand, eight hundred fifty-two".