21149528 has 8 divisors (see below), whose sum is σ = 39655380. Its totient is φ = 10574760.

The previous prime is 21149509. The next prime is 21149539. The reversal of 21149528 is 82594112.

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 21149494 and 21149503.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1321838 + ... + 1321853.

Almost surely, 2^21149528 is an apocalyptic number.

It is an amenable number.

21149528 is a deficient number, since it is larger than the sum of its proper divisors (18505852).

21149528 is a wasteful number, since it uses less digits than its factorization.

21149528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2643697 (or 2643693 counting only the distinct ones).

The product of its digits is 5760, while the sum is 32.

The square root of 21149528 is about 4598.8615982654. The cubic root of 21149528 is about 276.5456892737.

The spelling of 21149528 in words is "twenty-one million, one hundred forty-nine thousand, five hundred twenty-eight".