20690442 has 12 divisors (see below), whose sum is σ = 44829330. Its totient is φ = 6896808.

The previous prime is 20690441. The next prime is 20690443. The reversal of 20690442 is 24409602.

It is an interprime number because it is at equal distance from previous prime (20690441) and next prime (20690443).

It can be written as a sum of positive squares in only one way, i.e., 20439441 + 251001 = 4521^2 + 501^2 .

It is not an unprimeable number, because it can be changed into a prime (20690441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 574717 + ... + 574752.

Almost surely, 2^20690442 is an apocalyptic number.

20690442 is an abundant number, since it is smaller than the sum of its proper divisors (24138888).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20690442 is a wasteful number, since it uses less digits than its factorization.

20690442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1149477 (or 1149474 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 20690442 is about 4548.6747520569. The cubic root of 20690442 is about 274.5300712574.

The spelling of 20690442 in words is "twenty million, six hundred ninety thousand, four hundred forty-two".