21121321029 has 16 divisors (see below), whose sum is σ = 28225323840. Its totient is φ = 14049129600.

The previous prime is 21121321019. The next prime is 21121321031. The reversal of 21121321029 is 92012312112.

It is not a de Polignac number, because 21121321029 - 2¹² = 21121316933 is a prime.

It is a super-2 number, since 2×21121321029² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121321019) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5242914 + ... + 5246940.

It is an arithmetic number, because the mean of its divisors is an integer number (1764082740).

Almost surely, 2^21121321029 is an apocalyptic number.

It is an amenable number.

21121321029 is a deficient number, since it is larger than the sum of its proper divisors (7104002811).

21121321029 is a wasteful number, since it uses less digits than its factorization.

21121321029 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7540.

The product of its (nonzero) digits is 432, while the sum is 24.

The spelling of 21121321029 in words is "twenty-one billion, one hundred twenty-one million, three hundred twenty-one thousand, twenty-nine".