81670011 has 8 divisors (see below), whose sum is σ = 109615104. Its totient is φ = 54085800.

The previous prime is 81670007. The next prime is 81670019. The reversal of 81670011 is 11007618.

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

It is not a de Polignac number, because 81670011 - 2² = 81670007 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81670019) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 89691 + ... + 90596.

It is an arithmetic number, because the mean of its divisors is an integer number (13701888).

Almost surely, 2^81670011 is an apocalyptic number.

81670011 is a deficient number, since it is larger than the sum of its proper divisors (27945093).

81670011 is a wasteful number, since it uses less digits than its factorization.

81670011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180441.

The product of its (nonzero) digits is 336, while the sum is 24.

The square root of 81670011 is about 9037.1461756464. The cubic root of 81670011 is about 433.8645882063.

Adding to 81670011 its reverse (11007618), we get a palindrome (92677629).

The spelling of 81670011 in words is "eighty-one million, six hundred seventy thousand, eleven".