21020124434 has 16 divisors (see below), whose sum is σ = 31996348800. Its totient is φ = 10355700960.

The previous prime is 21020124431. The next prime is 21020124439. The reversal of 21020124434 is 43442102012.

It is not an unprimeable number, because it can be changed into a prime (21020124431) 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, 215387 + ... + 297374.

It is an arithmetic number, because the mean of its divisors is an integer number (1999771800).

Almost surely, 2^21020124434 is an apocalyptic number.

21020124434 is a deficient number, since it is larger than the sum of its proper divisors (10976224366).

21020124434 is a wasteful number, since it uses less digits than its factorization.

21020124434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 513065.

The product of its (nonzero) digits is 1536, while the sum is 23.

Adding to 21020124434 its reverse (43442102012), we get a palindrome (64462226446).

The spelling of 21020124434 in words is "twenty-one billion, twenty million, one hundred twenty-four thousand, four hundred thirty-four".