21670006 has 8 divisors (see below), whose sum is σ = 33038064. Its totient is φ = 10657320.

The previous prime is 21670003. The next prime is 21670007. The reversal of 21670006 is 60007612.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21670003) 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, 88690 + ... + 88933.

It is an arithmetic number, because the mean of its divisors is an integer number (4129758).

Almost surely, 2^21670006 is an apocalyptic number.

21670006 is a deficient number, since it is larger than the sum of its proper divisors (11368058).

21670006 is a wasteful number, since it uses less digits than its factorization.

21670006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177686.

The product of its (nonzero) digits is 504, while the sum is 22.

The square root of 21670006 is about 4655.1053693767. The cubic root of 21670006 is about 278.7958750669.

Adding to 21670006 its reverse (60007612), we get a palindrome (81677618).

The spelling of 21670006 in words is "twenty-one million, six hundred seventy thousand, six".