20897535 has 16 divisors (see below), whose sum is σ = 33633504. Its totient is φ = 11079552.

The previous prime is 20897533. The next prime is 20897543. The reversal of 20897535 is 53579802.

It is not a de Polignac number, because 20897535 - 2¹ = 20897533 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20897493 and 20897502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20897533) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1432 + ... + 6621.

It is an arithmetic number, because the mean of its divisors is an integer number (2102094).

Almost surely, 2^20897535 is an apocalyptic number.

20897535 is a deficient number, since it is larger than the sum of its proper divisors (12735969).

20897535 is a wasteful number, since it uses less digits than its factorization.

20897535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8234.

The product of its (nonzero) digits is 75600, while the sum is 39.

The square root of 20897535 is about 4571.3821761039. The cubic root of 20897535 is about 275.4429665328.

The spelling of 20897535 in words is "twenty million, eight hundred ninety-seven thousand, five hundred thirty-five".