21167357206 has 4 divisors (see below), whose sum is σ = 31751035812. Its totient is φ = 10583678602.

The previous prime is 21167357191. The next prime is 21167357219. The reversal of 21167357206 is 60275376112.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×21167357206² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5291839300 + ... + 5291839303.

It is an arithmetic number, because the mean of its divisors is an integer number (7937758953).

Almost surely, 2^21167357206 is an apocalyptic number.

21167357206 is a deficient number, since it is larger than the sum of its proper divisors (10583678606).

21167357206 is a wasteful number, since it uses less digits than its factorization.

21167357206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10583678605.

The product of its (nonzero) digits is 105840, while the sum is 40.

The spelling of 21167357206 in words is "twenty-one billion, one hundred sixty-seven million, three hundred fifty-seven thousand, two hundred six".