21872067 has 32 divisors (see below), whose sum is σ = 34406400. Its totient is φ = 12102048.

The previous prime is 21872029. The next prime is 21872087. The reversal of 21872067 is 76027812.

It is not a de Polignac number, because 21872067 - 2¹⁰ = 21871043 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21872027) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 157284 + ... + 157422.

It is an arithmetic number, because the mean of its divisors is an integer number (1075200).

Almost surely, 2^21872067 is an apocalyptic number.

21872067 is a deficient number, since it is larger than the sum of its proper divisors (12534333).

21872067 is a wasteful number, since it uses less digits than its factorization.

21872067 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 335.

The product of its (nonzero) digits is 9408, while the sum is 33.

The square root of 21872067 is about 4676.7581720675. The cubic root of 21872067 is about 279.6597354772.

Adding to 21872067 its reverse (76027812), we get a palindrome (97899879).

The spelling of 21872067 in words is "twenty-one million, eight hundred seventy-two thousand, sixty-seven".