21403234140 has 48 divisors (see below), whose sum is σ = 59959106592. Its totient is φ = 5704667136.

The previous prime is 21403234123. The next prime is 21403234169. The reversal of 21403234140 is 4143230412.

It is a self number, because there is not a number n which added to its sum of digits gives 21403234140.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32592 + ... + 209448.

It is an arithmetic number, because the mean of its divisors is an integer number (1249148054).

Almost surely, 2^21403234140 is an apocalyptic number.

21403234140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21403234140 is an abundant number, since it is smaller than the sum of its proper divisors (38555872452).

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

21403234140 is a wasteful number, since it uses less digits than its factorization.

21403234140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178886 (or 178884 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

Adding to 21403234140 its reverse (4143230412), we get a palindrome (25546464552).

The spelling of 21403234140 in words is "twenty-one billion, four hundred three million, two hundred thirty-four thousand, one hundred forty".