21276087 has 16 divisors (see below), whose sum is σ = 32524800. Its totient is φ = 12118752.

The previous prime is 21276083. The next prime is 21276109. The reversal of 21276087 is 78067212.

It is not a de Polignac number, because 21276087 - 2² = 21276083 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21276083) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5878 + ... + 8780.

It is an arithmetic number, because the mean of its divisors is an integer number (2032800).

Almost surely, 2^21276087 is an apocalyptic number.

21276087 is a deficient number, since it is larger than the sum of its proper divisors (11248713).

21276087 is a wasteful number, since it uses less digits than its factorization.

21276087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3262.

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

The square root of 21276087 is about 4612.6008932055. The cubic root of 21276087 is about 277.0962100686.

The spelling of 21276087 in words is "twenty-one million, two hundred seventy-six thousand, eighty-seven".