21123431033340 has 96 divisors (see below), whose sum is σ = 60143864901120. Its totient is φ = 5538631737600.

The previous prime is 21123431033329. The next prime is 21123431033351. The reversal of 21123431033340 is 4333013432112.

It is an interprime number because it is at equal distance from previous prime (21123431033329) and next prime (21123431033351).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 21123431033298 and 21123431033307.

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, 11471056 + ... + 13184535.

It is an arithmetic number, because the mean of its divisors is an integer number (626498592720).

Almost surely, 2^{21123431033340} is an apocalyptic number.

21123431033340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21123431033340 is an abundant number, since it is smaller than the sum of its proper divisors (39020433867780).

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

21123431033340 is a wasteful number, since it uses less digits than its factorization.

21123431033340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24655843 (or 24655841 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 30.

Adding to 21123431033340 its reverse (4333013432112), we get a palindrome (25456444465452).

The spelling of 21123431033340 in words is "twenty-one trillion, one hundred twenty-three billion, four hundred thirty-one million, thirty-three thousand, three hundred forty".