21171054 has 16 divisors (see below), whose sum is σ = 44570880. Its totient is φ = 6685560.

The previous prime is 21171049. The next prime is 21171089. The reversal of 21171054 is 45017112.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21171054.

It is a congruent 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, 92742 + ... + 92969.

It is an arithmetic number, because the mean of its divisors is an integer number (2785680).

Almost surely, 2^21171054 is an apocalyptic number.

21171054 is an abundant number, since it is smaller than the sum of its proper divisors (23399826).

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

21171054 is a wasteful number, since it uses less digits than its factorization.

21171054 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185735.

The product of its (nonzero) digits is 280, while the sum is 21.

The square root of 21171054 is about 4601.2013648611. The cubic root of 21171054 is about 276.6394802402.

Adding to 21171054 its reverse (45017112), we get a palindrome (66188166).

The spelling of 21171054 in words is "twenty-one million, one hundred seventy-one thousand, fifty-four".