21037037040 has 160 divisors (see below), whose sum is σ = 72512055360. Its totient is φ = 5605917696.

The previous prime is 21037037029. The next prime is 21037037057. The reversal of 21037037040 is 4073073012.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 21037036995 and 21037037013.

It is a congruent number.

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, 4311082 + ... + 4315958.

It is an arithmetic number, because the mean of its divisors is an integer number (453200346).

Almost surely, 2^21037037040 is an apocalyptic number.

21037037040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21037037040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36256027680).

21037037040 is an abundant number, since it is smaller than the sum of its proper divisors (51475018320).

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

21037037040 is a wasteful number, since it uses less digits than its factorization.

21037037040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6896 (or 6884 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 27.

The spelling of 21037037040 in words is "twenty-one billion, thirty-seven million, thirty-seven thousand, forty".