20535381 has 24 divisors (see below), whose sum is σ = 31025280. Its totient is φ = 13075776.

The previous prime is 20535379. The next prime is 20535413. The reversal of 20535381 is 18353502.

It is not a de Polignac number, because 20535381 - 2¹ = 20535379 is a prime.

It is a super-2 number, since 2×20535381² = 843403745630322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20536381) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17625 + ... + 18753.

It is an arithmetic number, because the mean of its divisors is an integer number (1292720).

Almost surely, 2^20535381 is an apocalyptic number.

It is an amenable number.

20535381 is a deficient number, since it is larger than the sum of its proper divisors (10489899).

20535381 is a wasteful number, since it uses less digits than its factorization.

20535381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1225 (or 1222 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 20535381 is about 4531.5980624941. The cubic root of 20535381 is about 273.8425445535.

Adding to 20535381 its reverse (18353502), we get a palindrome (38888883).

The spelling of 20535381 in words is "twenty million, five hundred thirty-five thousand, three hundred eighty-one".