81210602 has 24 divisors (see below), whose sum is σ = 135760548. Its totient is φ = 36400320.

The previous prime is 81210601. The next prime is 81210629. The reversal of 81210602 is 20601218.

It can be written as a sum of positive squares in 2 ways, for example, as 77246521 + 3964081 = 8789^2 + 1991^2 .

It is not an unprimeable number, because it can be changed into a prime (81210601) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15368 + ... + 19964.

Almost surely, 2^81210602 is an apocalyptic number.

81210602 is a deficient number, since it is larger than the sum of its proper divisors (54549946).

81210602 is a wasteful number, since it uses less digits than its factorization.

81210602 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4694 (or 4683 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 20.

The square root of 81210602 is about 9011.6925158374. The cubic root of 81210602 is about 433.0495350172.

The spelling of 81210602 in words is "eighty-one million, two hundred ten thousand, six hundred two".