21117052 has 24 divisors (see below), whose sum is σ = 40642560. Its totient is φ = 9520560.

The previous prime is 21117049. The next prime is 21117067. The reversal of 21117052 is 25071112.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3699 + ... + 7477.

It is an arithmetic number, because the mean of its divisors is an integer number (1693440).

Almost surely, 2^21117052 is an apocalyptic number.

21117052 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21117052 is a deficient number, since it is larger than the sum of its proper divisors (19525508).

21117052 is a wasteful number, since it uses less digits than its factorization.

21117052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3921 (or 3919 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 19.

The square root of 21117052 is about 4595.3293679561. The cubic root of 21117052 is about 276.4040675365.

Adding to 21117052 its reverse (25071112), we get a palindrome (46188164).

The spelling of 21117052 in words is "twenty-one million, one hundred seventeen thousand, fifty-two".