21223645151 has 4 divisors (see below), whose sum is σ = 21334763904. Its totient is φ = 21112526400.

The previous prime is 21223645097. The next prime is 21223645153. The reversal of 21223645151 is 15154632212.

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

It is a cyclic number.

It is not a de Polignac number, because 21223645151 - 2¹⁸ = 21223383007 is a prime.

It is a super-2 number, since 2×21223645151² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21223645153) 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, 55559090 + ... + 55559471.

It is an arithmetic number, because the mean of its divisors is an integer number (5333690976).

Almost surely, 2^21223645151 is an apocalyptic number.

21223645151 is a deficient number, since it is larger than the sum of its proper divisors (111118753).

21223645151 is a wasteful number, since it uses less digits than its factorization.

21223645151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111118752.

The product of its digits is 14400, while the sum is 32.

The spelling of 21223645151 in words is "twenty-one billion, two hundred twenty-three million, six hundred forty-five thousand, one hundred fifty-one".