21253411040 has 24 divisors (see below), whose sum is σ = 50211183960. Its totient is φ = 8501364352.

The previous prime is 21253411037. The next prime is 21253411063. The reversal of 21253411040 is 4011435212.

It is a junction number, because it is equal to n+sod(n) for n = 21253410997 and 21253411015.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66416750 + ... + 66417069.

It is an arithmetic number, because the mean of its divisors is an integer number (2092132665).

Almost surely, 2^21253411040 is an apocalyptic number.

21253411040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21253411040 is an abundant number, since it is smaller than the sum of its proper divisors (28957772920).

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

21253411040 is a wasteful number, since it uses less digits than its factorization.

21253411040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132833834 (or 132833826 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

Adding to 21253411040 its reverse (4011435212), we get a palindrome (25264846252).

The spelling of 21253411040 in words is "twenty-one billion, two hundred fifty-three million, four hundred eleven thousand, forty".