81210970 has 8 divisors (see below), whose sum is σ = 146179764. Its totient is φ = 32484384.

The previous prime is 81210923. The next prime is 81210977. The reversal of 81210970 is 7901218.

It can be written as a sum of positive squares in 2 ways, for example, as 75916369 + 5294601 = 8713^2 + 2301^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (81210977) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4060539 + ... + 4060558.

Almost surely, 2^81210970 is an apocalyptic number.

81210970 is a deficient number, since it is larger than the sum of its proper divisors (64968794).

81210970 is a wasteful number, since it uses less digits than its factorization.

81210970 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8121104.

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 81210970 is about 9011.7129337324. The cubic root of 81210970 is about 433.0501891271.

The spelling of 81210970 in words is "eighty-one million, two hundred ten thousand, nine hundred seventy".