21046519 has 4 divisors (see below), whose sum is σ = 22665496. Its totient is φ = 19427544.

The previous prime is 21046513. The next prime is 21046537. The reversal of 21046519 is 91564012.

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 21046519 - 2¹³ = 21038327 is a prime.

It is a super-2 number, since 2×21046519² = 885911924034722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21046513) 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, 809469 + ... + 809494.

It is an arithmetic number, because the mean of its divisors is an integer number (5666374).

Almost surely, 2^21046519 is an apocalyptic number.

21046519 is a deficient number, since it is larger than the sum of its proper divisors (1618977).

21046519 is a wasteful number, since it uses less digits than its factorization.

21046519 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1618976.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 21046519 is about 4587.6485262060. The cubic root of 21046519 is about 276.0959854835.

The spelling of 21046519 in words is "twenty-one million, forty-six thousand, five hundred nineteen".