21232143 has 12 divisors (see below), whose sum is σ = 30708600. Its totient is φ = 14136336.

The previous prime is 21232121. The next prime is 21232157. The reversal of 21232143 is 34123212.

It is not a de Polignac number, because 21232143 - 2⁹ = 21231631 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a zygodrome in base 4.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21232103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12933 + ... + 14481.

It is an arithmetic number, because the mean of its divisors is an integer number (2559050).

Almost surely, 2^21232143 is an apocalyptic number.

21232143 is a deficient number, since it is larger than the sum of its proper divisors (9476457).

21232143 is a wasteful number, since it uses less digits than its factorization.

21232143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3078 (or 3075 counting only the distinct ones).

The product of its digits is 288, while the sum is 18.

The square root of 21232143 is about 4607.8349579819. The cubic root of 21232143 is about 276.9053054657.

Adding to 21232143 its reverse (34123212), we get a palindrome (55355355).

It can be divided in two parts, 21 and 232143, that multiplied together give a triangular number (4875003 = T₃₁₂₂).

The spelling of 21232143 in words is "twenty-one million, two hundred thirty-two thousand, one hundred forty-three".