21231121011 has 8 divisors (see below), whose sum is σ = 28308983040. Its totient is φ = 14153669832.

The previous prime is 21231120971. The next prime is 21231121027. The reversal of 21231121011 is 11012113212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21231121011 - 2¹⁴ = 21231104627 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21231121081) 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 7 ways as a sum of consecutive naturals, for example, 50530 + ... + 212168.

It is an arithmetic number, because the mean of its divisors is an integer number (3538622880).

Almost surely, 2^21231121011 is an apocalyptic number.

21231121011 is a deficient number, since it is larger than the sum of its proper divisors (7077862029).

21231121011 is a wasteful number, since it uses less digits than its factorization.

21231121011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205425.

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 21231121011 its reverse (11012113212), we get a palindrome (32243234223).

The spelling of 21231121011 in words is "twenty-one billion, two hundred thirty-one million, one hundred twenty-one thousand, eleven".