21320104040040 has 128 divisors (see below), whose sum is σ = 69489897200640. Its totient is φ = 5201582862336.

The previous prime is 21320104040029. The next prime is 21320104040041. The reversal of 21320104040040 is 4004040102312.

It is a junction number, because it is equal to n+sod(n) for n = 21320104039989 and 21320104040016.

It is not an unprimeable number, because it can be changed into a prime (21320104040041) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 60295992 + ... + 60648551.

It is an arithmetic number, because the mean of its divisors is an integer number (542889821880).

Almost surely, 2^{21320104040040} is an apocalyptic number.

21320104040040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21320104040040 is an abundant number, since it is smaller than the sum of its proper divisors (48169793160600).

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

21320104040040 is a wasteful number, since it uses less digits than its factorization.

21320104040040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120944683 (or 120944679 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

Adding to 21320104040040 its reverse (4004040102312), we get a palindrome (25324144142352).

The spelling of 21320104040040 in words is "twenty-one trillion, three hundred twenty billion, one hundred four million, forty thousand, forty".