20993145 has 8 divisors (see below), whose sum is σ = 33589056. Its totient is φ = 11196336.

The previous prime is 20993131. The next prime is 20993149. The reversal of 20993145 is 54139902.

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

It is not a de Polignac number, because 20993145 - 2⁷ = 20993017 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20993149) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 699757 + ... + 699786.

It is an arithmetic number, because the mean of its divisors is an integer number (4198632).

Almost surely, 2^20993145 is an apocalyptic number.

It is an amenable number.

20993145 is a deficient number, since it is larger than the sum of its proper divisors (12595911).

20993145 is a wasteful number, since it uses less digits than its factorization.

20993145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1399551.

The product of its (nonzero) digits is 9720, while the sum is 33.

The square root of 20993145 is about 4581.8276920897. The cubic root of 20993145 is about 275.8623946485.

The spelling of 20993145 in words is "twenty million, nine hundred ninety-three thousand, one hundred forty-five".