21234021212040 has 128 divisors (see below), whose sum is σ = 78402539900160. Its totient is φ = 4480145132544.

The previous prime is 21234021212023. The next prime is 21234021212123. The reversal of 21234021212040 is 4021212043212.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 21234021212040.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 972242799 + ... + 972264638.

It is an arithmetic number, because the mean of its divisors is an integer number (612519842970).

Almost surely, 2^{21234021212040} is an apocalyptic number.

21234021212040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21234021212040 is an abundant number, since it is smaller than the sum of its proper divisors (57168518688120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21234021212040 is a wasteful number, since it uses less digits than its factorization.

21234021212040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1944507471 (or 1944507467 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

Adding to 21234021212040 its reverse (4021212043212), we get a palindrome (25255233255252).

The spelling of 21234021212040 in words is "twenty-one trillion, two hundred thirty-four billion, twenty-one million, two hundred twelve thousand, forty".