21451042012 has 6 divisors (see below), whose sum is σ = 37539323528. Its totient is φ = 10725521004.

The previous prime is 21451042001. The next prime is 21451042073. The reversal of 21451042012 is 21024015412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2681380248 + ... + 2681380255.

Almost surely, 2^21451042012 is an apocalyptic number.

It is an amenable number.

21451042012 is a deficient number, since it is larger than the sum of its proper divisors (16088281516).

21451042012 is a wasteful number, since it uses less digits than its factorization.

21451042012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5362760507 (or 5362760505 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 22.

Adding to 21451042012 its reverse (21024015412), we get a palindrome (42475057424).

The spelling of 21451042012 in words is "twenty-one billion, four hundred fifty-one million, forty-two thousand, twelve".