21019892 has 12 divisors (see below), whose sum is σ = 36989316. Its totient is φ = 10451520.

The previous prime is 21019879. The next prime is 21019903. The reversal of 21019892 is 29891012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 2735716 + 18284176 = 1654^2 + 4276^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13793 + ... + 15240.

It is an arithmetic number, because the mean of its divisors is an integer number (3082443).

Almost surely, 2^21019892 is an apocalyptic number.

It is an amenable number.

21019892 is a deficient number, since it is larger than the sum of its proper divisors (15969424).

21019892 is a wasteful number, since it uses less digits than its factorization.

21019892 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29218 (or 29216 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 32.

The square root of 21019892 is about 4584.7455763652. The cubic root of 21019892 is about 275.9795020834.

It can be divided in two parts, 210 and 19892, that added together give a palindrome (20102).

The spelling of 21019892 in words is "twenty-one million, nineteen thousand, eight hundred ninety-two".