21050755 has 16 divisors (see below), whose sum is σ = 27661824. Its totient is φ = 15251680.

The previous prime is 21050749. The next prime is 21050801. The reversal of 21050755 is 55705012.

It is a happy number.

It is not a de Polignac number, because 21050755 - 2³ = 21050747 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18534 + ... + 19636.

It is an arithmetic number, because the mean of its divisors is an integer number (1728864).

Almost surely, 2^21050755 is an apocalyptic number.

21050755 is a deficient number, since it is larger than the sum of its proper divisors (6611069).

21050755 is a wasteful number, since it uses less digits than its factorization.

21050755 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1466.

The product of its (nonzero) digits is 1750, while the sum is 25.

The square root of 21050755 is about 4588.1101774042. The cubic root of 21050755 is about 276.1145073768.

Adding to 21050755 its reverse (55705012), we get a palindrome (76755767).

The spelling of 21050755 in words is "twenty-one million, fifty thousand, seven hundred fifty-five".