21003103121 has 32 divisors (see below), whose sum is σ = 28242778368. Its totient is φ = 15084195840.

The previous prime is 21003103049. The next prime is 21003103133. The reversal of 21003103121 is 12130130012.

It is not a de Polignac number, because 21003103121 - 2²² = 20998908817 is a prime.

It is a super-2 number, since 2×21003103121² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21003103096 and 21003103105.

It is not an unprimeable number, because it can be changed into a prime (21003103151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 658085 + ... + 689261.

It is an arithmetic number, because the mean of its divisors is an integer number (882586824).

Almost surely, 2^21003103121 is an apocalyptic number.

It is an amenable number.

21003103121 is a deficient number, since it is larger than the sum of its proper divisors (7239675247).

21003103121 is a wasteful number, since it uses less digits than its factorization.

21003103121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31881.

The product of its (nonzero) digits is 36, while the sum is 14.

Adding to 21003103121 its reverse (12130130012), we get a palindrome (33133233133).

The spelling of 21003103121 in words is "twenty-one billion, three million, one hundred three thousand, one hundred twenty-one".