21293611040 has 96 divisors (see below), whose sum is σ = 54317193840. Its totient is φ = 7841746944.

The previous prime is 21293611039. The next prime is 21293611081. The reversal of 21293611040 is 4011639212.

It can be written as a sum of positive squares in 8 ways, for example, as 4079121424 + 17214489616 = 63868^2 + 131204^2 .

It is a super-2 number, since 2×21293611040² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21293610994 and 21293611012.

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, 795962 + ... + 822278.

Almost surely, 2^21293611040 is an apocalyptic number.

21293611040 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 21293611040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27158596920).

21293611040 is an abundant number, since it is smaller than the sum of its proper divisors (33023582800).

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

21293611040 is a wasteful number, since it uses less digits than its factorization.

21293611040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26734 (or 26726 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 29.

The spelling of 21293611040 in words is "twenty-one billion, two hundred ninety-three million, six hundred eleven thousand, forty".