21031220134 has 16 divisors (see below), whose sum is σ = 31691142720. Its totient is φ = 10467613800.

The previous prime is 21031220129. The next prime is 21031220173. The reversal of 21031220134 is 43102213012.

It is a happy number.

21031220134 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 369909 + ... + 422959.

It is an arithmetic number, because the mean of its divisors is an integer number (1980696420).

Almost surely, 2^21031220134 is an apocalyptic number.

21031220134 is a deficient number, since it is larger than the sum of its proper divisors (10659922586).

21031220134 is a wasteful number, since it uses less digits than its factorization.

21031220134 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53955.

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

Adding to 21031220134 its reverse (43102213012), we get a palindrome (64133433146).

It can be divided in two parts, 21031 and 220134, that added together give a triangular number (241165 = T₆₉₄).

The spelling of 21031220134 in words is "twenty-one billion, thirty-one million, two hundred twenty thousand, one hundred thirty-four".