21143431123240 has 32 divisors (see below), whose sum is σ = 47572914142080. Its totient is φ = 8457337940032.

The previous prime is 21143431123211. The next prime is 21143431123261. The reversal of 21143431123240 is 4232113434112.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10339629 + ... + 12214531.

It is an arithmetic number, because the mean of its divisors is an integer number (1486653566940).

Almost surely, 2^{21143431123240} is an apocalyptic number.

21143431123240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21143431123240 is an abundant number, since it is smaller than the sum of its proper divisors (26429483018840).

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

21143431123240 is a wasteful number, since it uses less digits than its factorization.

21143431123240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2156841 (or 2156837 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 31.

Adding to 21143431123240 its reverse (4232113434112), we get a palindrome (25375544557352).

The spelling of 21143431123240 in words is "twenty-one trillion, one hundred forty-three billion, four hundred thirty-one million, one hundred twenty-three thousand, two hundred forty".