21221210140 has 48 divisors (see below), whose sum is σ = 49289702112. Its totient is φ = 7623749376.

The previous prime is 21221210137. The next prime is 21221210147. The reversal of 21221210140 is 4101212212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221210147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1093354 + ... + 1112593.

It is an arithmetic number, because the mean of its divisors is an integer number (1026868794).

Almost surely, 2^21221210140 is an apocalyptic number.

21221210140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221210140 is an abundant number, since it is smaller than the sum of its proper divisors (28068491972).

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

21221210140 is a wasteful number, since it uses less digits than its factorization.

21221210140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2206006 (or 2206004 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21221210140 its reverse (4101212212), we get a palindrome (25322422352).

It can be divided in two parts, 21221 and 210140, that added together give a square (231361 = 481²).

The spelling of 21221210140 in words is "twenty-one billion, two hundred twenty-one million, two hundred ten thousand, one hundred forty".