21502162166 has 8 divisors (see below), whose sum is σ = 33124952640. Its totient is φ = 10460511288.

The previous prime is 21502162151. The next prime is 21502162183. The reversal of 21502162166 is 66126120512.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 145284806 + ... + 145284953.

It is an arithmetic number, because the mean of its divisors is an integer number (4140619080).

Almost surely, 2^21502162166 is an apocalyptic number.

21502162166 is a deficient number, since it is larger than the sum of its proper divisors (11622790474).

21502162166 is a wasteful number, since it uses less digits than its factorization.

21502162166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 290569798.

The product of its (nonzero) digits is 8640, while the sum is 32.

Adding to 21502162166 its reverse (66126120512), we get a palindrome (87628282678).

The spelling of 21502162166 in words is "twenty-one billion, five hundred two million, one hundred sixty-two thousand, one hundred sixty-six".