21716006 has 16 divisors (see below), whose sum is σ = 35168784. Its totient is φ = 9997344.

The previous prime is 21715999. The next prime is 21716017. The reversal of 21716006 is 60061712.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12800 + ... + 14396.

It is an arithmetic number, because the mean of its divisors is an integer number (2198049).

Almost surely, 2^21716006 is an apocalyptic number.

21716006 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21716006 is a deficient number, since it is larger than the sum of its proper divisors (13452778).

21716006 is a wasteful number, since it uses less digits than its factorization.

21716006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2135.

The product of its (nonzero) digits is 504, while the sum is 23.

The square root of 21716006 is about 4660.0435620281. The cubic root of 21716006 is about 278.9930069375.

Adding to 21716006 its reverse (60061712), we get a palindrome (81777718).

The spelling of 21716006 in words is "twenty-one million, seven hundred sixteen thousand, six".