20690930 has 16 divisors (see below), whose sum is σ = 40108824. Its totient is φ = 7639680.

The previous prime is 20690927. The next prime is 20690939. The reversal of 20690930 is 3909602.

It can be written as a sum of positive squares in 4 ways, for example, as 17447329 + 3243601 = 4177^2 + 1801^2 .

It is a super-2 number, since 2×20690930² = 856229168529800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20690893 and 20690902.

It is not an unprimeable number, because it can be changed into a prime (20690939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79451 + ... + 79710.

Almost surely, 2^20690930 is an apocalyptic number.

20690930 is a deficient number, since it is larger than the sum of its proper divisors (19417894).

20690930 is a wasteful number, since it uses less digits than its factorization.

20690930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159181.

The product of its (nonzero) digits is 2916, while the sum is 29.

The square root of 20690930 is about 4548.7283937382. The cubic root of 20690930 is about 274.5322295748.

The spelling of 20690930 in words is "twenty million, six hundred ninety thousand, nine hundred thirty".