21428995 has 16 divisors (see below), whose sum is σ = 29873088. Its totient is φ = 14451840.

The previous prime is 21428989. The next prime is 21429011. The reversal of 21428995 is 59982412.

It is not a de Polignac number, because 21428995 - 2⁵ = 21428963 is a prime.

It is an unprimeable number.

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, 2884 + ... + 7153.

It is an arithmetic number, because the mean of its divisors is an integer number (1867068).

Almost surely, 2^21428995 is an apocalyptic number.

21428995 is a deficient number, since it is larger than the sum of its proper divisors (8444093).

21428995 is a wasteful number, since it uses less digits than its factorization.

21428995 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10110.

The product of its digits is 51840, while the sum is 40.

The square root of 21428995 is about 4629.1462495799. The cubic root of 21428995 is about 277.7584422393.

The spelling of 21428995 in words is "twenty-one million, four hundred twenty-eight thousand, nine hundred ninety-five".