21115514023351 has 16 divisors (see below), whose sum is σ = 23830945689600. Its totient is φ = 18532807020000.

The previous prime is 21115514023301. The next prime is 21115514023379. The reversal of 21115514023351 is 15332041551112.

It is a cyclic number.

It is not a de Polignac number, because 21115514023351 - 2¹³ = 21115514015159 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21115514023301) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2890726 + ... + 7112476.

It is an arithmetic number, because the mean of its divisors is an integer number (1489434105600).

Almost surely, 2^{21115514023351} is an apocalyptic number.

21115514023351 is a deficient number, since it is larger than the sum of its proper divisors (2715431666249).

21115514023351 is a wasteful number, since it uses less digits than its factorization.

21115514023351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4237470.

The product of its (nonzero) digits is 18000, while the sum is 34.

Adding to 21115514023351 its reverse (15332041551112), we get a palindrome (36447555574463).

The spelling of 21115514023351 in words is "twenty-one trillion, one hundred fifteen billion, five hundred fourteen million, twenty-three thousand, three hundred fifty-one".