21454421012 has 12 divisors (see below), whose sum is σ = 37709191380. Its totient is φ = 10680366336.

The previous prime is 21454421003. The next prime is 21454421057. The reversal of 21454421012 is 21012445412.

It can be written as a sum of positive squares in 2 ways, for example, as 16971315076 + 4483105936 = 130274^2 + 66956^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11710013 + ... + 11711844.

It is an arithmetic number, because the mean of its divisors is an integer number (3142432615).

Almost surely, 2^21454421012 is an apocalyptic number.

It is an amenable number.

21454421012 is a deficient number, since it is larger than the sum of its proper divisors (16254770368).

21454421012 is a wasteful number, since it uses less digits than its factorization.

21454421012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23422090 (or 23422088 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 26.

Adding to 21454421012 its reverse (21012445412), we get a palindrome (42466866424).

The spelling of 21454421012 in words is "twenty-one billion, four hundred fifty-four million, four hundred twenty-one thousand, twelve".