21154303171 has 8 divisors (see below), whose sum is σ = 21305135888. Its totient is φ = 21003948000.

The previous prime is 21154303147. The next prime is 21154303207. The reversal of 21154303171 is 17130345112.

21154303171 = T₁₁₈₇₅₄ + T₁₁₈₇₅₅ + T₁₁₈₇₅₆.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a 5-Lehmer number, since φ(21154303171) divides (21154303171-1)⁵.

It is a cyclic number.

It is not a de Polignac number, because 21154303171 - 2²³ = 21145914563 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21154303571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30240 + ... + 207901.

It is an arithmetic number, because the mean of its divisors is an integer number (2663141986).

Almost surely, 2^21154303171 is an apocalyptic number.

21154303171 is the 118756-th centered triangular number.

21154303171 is a deficient number, since it is larger than the sum of its proper divisors (150832717).

21154303171 is a wasteful number, since it uses less digits than its factorization.

21154303171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238773.

The product of its (nonzero) digits is 2520, while the sum is 28.

Adding to 21154303171 its reverse (17130345112), we get a palindrome (38284648283).

The spelling of 21154303171 in words is "twenty-one billion, one hundred fifty-four million, three hundred three thousand, one hundred seventy-one".