28219632169 has 3 divisors (see below), whose sum is σ = 28219800157. Its totient is φ = 28219464182.

The previous prime is 28219632163. The next prime is 28219632211. The reversal of 28219632169 is 96123691282.

The square root of 28219632169 is 167987.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 28219632169 - 2¹¹ = 28219630121 is a prime.

It is a super-2 number, since 2×28219632169² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28219632163) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 83994 + ... + 251980.

Almost surely, 2^28219632169 is an apocalyptic number.

28219632169 is the 167987-th square number.

28219632169 is the 83994-th centered octagonal number.

It is an amenable number.

28219632169 is a deficient number, since it is larger than the sum of its proper divisors (167988).

28219632169 is an frugal number, since it uses more digits than its factorization.

28219632169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 335974 (or 167987 counting only the distinct ones).

The product of its digits is 559872, while the sum is 49.

Multiplying 28219632169 by its sum of digits (49), we get a square (1382761976281 = 1175909²).

The spelling of 28219632169 in words is "twenty-eight billion, two hundred nineteen million, six hundred thirty-two thousand, one hundred sixty-nine".