21233021401 has 4 divisors (see below), whose sum is σ = 21233911972. Its totient is φ = 21232130832.

The previous prime is 21233021399. The next prime is 21233021443. The reversal of 21233021401 is 10412033212.

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 13824115776 + 7408905625 = 117576^2 + 86075^2 .

It is a cyclic number.

It is not a de Polignac number, because 21233021401 - 2¹ = 21233021399 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21233021701) 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, 408510 + ... + 457543.

It is an arithmetic number, because the mean of its divisors is an integer number (5308477993).

Almost surely, 2^21233021401 is an apocalyptic number.

It is an amenable number.

21233021401 is a deficient number, since it is larger than the sum of its proper divisors (890571).

21233021401 is an equidigital number, since it uses as much as digits as its factorization.

21233021401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 890570.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21233021401 its reverse (10412033212), we get a palindrome (31645054613).

The spelling of 21233021401 in words is "twenty-one billion, two hundred thirty-three million, twenty-one thousand, four hundred one".