21421204012 has 24 divisors (see below), whose sum is σ = 40394195856. Its totient is φ = 9880963008.

The previous prime is 21421204009. The next prime is 21421204027. The reversal of 21421204012 is 21040212412.

It is a super-2 number, since 2×21421204012² (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, 28738 + ... + 208969.

It is an arithmetic number, because the mean of its divisors is an integer number (1683091494).

Almost surely, 2^21421204012 is an apocalyptic number.

It is an amenable number.

21421204012 is a deficient number, since it is larger than the sum of its proper divisors (18972991844).

21421204012 is a wasteful number, since it uses less digits than its factorization.

21421204012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239457 (or 239455 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 21421204012 its reverse (21040212412), we get a palindrome (42461416424).

The spelling of 21421204012 in words is "twenty-one billion, four hundred twenty-one million, two hundred four thousand, twelve".