21380552 has 16 divisors (see below), whose sum is σ = 40141440. Its totient is φ = 10676176.

The previous prime is 21380549. The next prime is 21380573. The reversal of 21380552 is 25508312.

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, 7613 + ... + 10035.

It is an arithmetic number, because the mean of its divisors is an integer number (2508840).

Almost surely, 2^21380552 is an apocalyptic number.

It is an amenable number.

21380552 is a deficient number, since it is larger than the sum of its proper divisors (18760888).

21380552 is a wasteful number, since it uses less digits than its factorization.

21380552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3532 (or 3528 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 21380552 is about 4623.9108987955. The cubic root of 21380552 is about 277.5489814249.

Adding to 21380552 its reverse (25508312), we get a palindrome (46888864).

The spelling of 21380552 in words is "twenty-one million, three hundred eighty thousand, five hundred fifty-two".