21357735 has 32 divisors (see below), whose sum is σ = 39439872. Its totient is φ = 9667200.

The previous prime is 21357719. The next prime is 21357773. The reversal of 21357735 is 53775312.

It is not a de Polignac number, because 21357735 - 2⁴ = 21357719 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21357696 and 21357705.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10285 + ... + 12185.

It is an arithmetic number, because the mean of its divisors is an integer number (1232496).

Almost surely, 2^21357735 is an apocalyptic number.

21357735 is a deficient number, since it is larger than the sum of its proper divisors (18082137).

21357735 is a wasteful number, since it uses less digits than its factorization.

21357735 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2023.

The product of its digits is 22050, while the sum is 33.

The square root of 21357735 is about 4621.4429564802. The cubic root of 21357735 is about 277.4502142647.

It can be divided in two parts, 2135 and 7735, that added together give a triangular number (9870 = T₁₄₀).

The spelling of 21357735 in words is "twenty-one million, three hundred fifty-seven thousand, seven hundred thirty-five".