20998135 has 16 divisors (see below), whose sum is σ = 26928000. Its totient is φ = 15672096.

The previous prime is 20998093. The next prime is 20998139. The reversal of 20998135 is 53189902.

It is a cyclic number.

It is not a de Polignac number, because 20998135 - 2⁷ = 20998007 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20998094 and 20998103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20998139) 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, 4716 + ... + 8014.

It is an arithmetic number, because the mean of its divisors is an integer number (1683000).

Almost surely, 2^20998135 is an apocalyptic number.

20998135 is a deficient number, since it is larger than the sum of its proper divisors (5929865).

20998135 is a wasteful number, since it uses less digits than its factorization.

20998135 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3390.

The product of its (nonzero) digits is 19440, while the sum is 37.

The square root of 20998135 is about 4582.3722022551. The cubic root of 20998135 is about 275.8842501049.

The spelling of 20998135 in words is "twenty million, nine hundred ninety-eight thousand, one hundred thirty-five".