21004212412 has 6 divisors (see below), whose sum is σ = 36757371728. Its totient is φ = 10502106204.

The previous prime is 21004212391. The next prime is 21004212413. The reversal of 21004212412 is 21421240012.

It is a self number, because there is not a number n which added to its sum of digits gives 21004212412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21004212413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2625526548 + ... + 2625526555.

Almost surely, 2^21004212412 is an apocalyptic number.

It is an amenable number.

21004212412 is a deficient number, since it is larger than the sum of its proper divisors (15753159316).

21004212412 is a wasteful number, since it uses less digits than its factorization.

21004212412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5251053107 (or 5251053105 counting only the distinct ones).

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

Adding to 21004212412 its reverse (21421240012), we get a palindrome (42425452424).

The spelling of 21004212412 in words is "twenty-one billion, four million, two hundred twelve thousand, four hundred twelve".