21221145134 has 16 divisors (see below), whose sum is σ = 36995702400. Its totient is φ = 8940627384.

The previous prime is 21221145133. The next prime is 21221145149. The reversal of 21221145134 is 43154112212.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221145133) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12844904 + ... + 12846555.

It is an arithmetic number, because the mean of its divisors is an integer number (2312231400).

Almost surely, 2^21221145134 is an apocalyptic number.

21221145134 is a deficient number, since it is larger than the sum of its proper divisors (15774557266).

21221145134 is a wasteful number, since it uses less digits than its factorization.

21221145134 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25691527.

The product of its digits is 1920, while the sum is 26.

Adding to 21221145134 its reverse (43154112212), we get a palindrome (64375257346).

The spelling of 21221145134 in words is "twenty-one billion, two hundred twenty-one million, one hundred forty-five thousand, one hundred thirty-four".