21252667 has 8 divisors (see below), whose sum is σ = 22225824. Its totient is φ = 20283648.

The previous prime is 21252653. The next prime is 21252677. The reversal of 21252667 is 76625212.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21252667 is a prime.

It is a super-2 number, since 2×21252667² = 903351709225778, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21252607) by changing a digit.

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, 14793 + ... + 16165.

It is an arithmetic number, because the mean of its divisors is an integer number (2778228).

Almost surely, 2^21252667 is an apocalyptic number.

21252667 is a deficient number, since it is larger than the sum of its proper divisors (973157).

21252667 is a wasteful number, since it uses less digits than its factorization.

21252667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2069.

The product of its digits is 10080, while the sum is 31.

The square root of 21252667 is about 4610.0614963360. The cubic root of 21252667 is about 276.9945000146.

Adding to 21252667 its reverse (76625212), we get a palindrome (97877879).

The spelling of 21252667 in words is "twenty-one million, two hundred fifty-two thousand, six hundred sixty-seven".