20989135 has 8 divisors (see below), whose sum is σ = 26668656. Its totient is φ = 15803520.

The previous prime is 20989103. The next prime is 20989147. The reversal of 20989135 is 53198902.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20989135 - 2⁵ = 20989103 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20989094 and 20989103.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 123381 + ... + 123550.

It is an arithmetic number, because the mean of its divisors is an integer number (3333582).

Almost surely, 2^20989135 is an apocalyptic number.

20989135 is a deficient number, since it is larger than the sum of its proper divisors (5679521).

20989135 is a wasteful number, since it uses less digits than its factorization.

20989135 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 246953.

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

The square root of 20989135 is about 4581.3900728927. The cubic root of 20989135 is about 275.8448289361.

The spelling of 20989135 in words is "twenty million, nine hundred eighty-nine thousand, one hundred thirty-five".