21326233477 has 4 divisors (see below), whose sum is σ = 21327987916. Its totient is φ = 21324479040.

The previous prime is 21326233471. The next prime is 21326233501. The reversal of 21326233477 is 77433262312.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 8244821601 + 13081411876 = 90801^2 + 114374^2 .

It is a cyclic number.

It is not a de Polignac number, because 21326233477 - 2¹¹ = 21326231429 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21326233471) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 858858 + ... + 883339.

It is an arithmetic number, because the mean of its divisors is an integer number (5331996979).

Almost surely, 2^21326233477 is an apocalyptic number.

It is an amenable number.

21326233477 is a deficient number, since it is larger than the sum of its proper divisors (1754439).

21326233477 is a wasteful number, since it uses less digits than its factorization.

21326233477 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1754438.

The product of its digits is 254016, while the sum is 40.

Adding to 21326233477 its reverse (77433262312), we get a palindrome (98759495789).

The spelling of 21326233477 in words is "twenty-one billion, three hundred twenty-six million, two hundred thirty-three thousand, four hundred seventy-seven".