21219891212 has 24 divisors (see below), whose sum is σ = 40004782272. Its totient is φ = 9790502400.

The previous prime is 21219891169. The next prime is 21219891247.

21219891212 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×21219891212² (a number of 21 digits) contains 22 as substring.

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, 91037 + ... + 225227.

It is an arithmetic number, because the mean of its divisors is an integer number (1666865928).

Almost surely, 2^21219891212 is an apocalyptic number.

It is an amenable number.

21219891212 is a deficient number, since it is larger than the sum of its proper divisors (18784891060).

21219891212 is a wasteful number, since it uses less digits than its factorization.

21219891212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137249 (or 137247 counting only the distinct ones).

The product of its digits is 10368, while the sum is 38.

The spelling of 21219891212 in words is "twenty-one billion, two hundred nineteen million, eight hundred ninety-one thousand, two hundred twelve".