21260167 has 4 divisors (see below), whose sum is σ = 21279760. Its totient is φ = 21240576.

The previous prime is 21260153. The next prime is 21260171. The reversal of 21260167 is 76106212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21260167 - 2⁷ = 21260039 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 (21260117) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8067 + ... + 10372.

It is an arithmetic number, because the mean of its divisors is an integer number (5319940).

Almost surely, 2^21260167 is an apocalyptic number.

21260167 is a deficient number, since it is larger than the sum of its proper divisors (19593).

21260167 is a wasteful number, since it uses less digits than its factorization.

21260167 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19592.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 21260167 is about 4610.8748627565. The cubic root of 21260167 is about 277.0270796813.

Adding to 21260167 its reverse (76106212), we get a palindrome (97366379).

The spelling of 21260167 in words is "twenty-one million, two hundred sixty thousand, one hundred sixty-seven".