20897494 has 8 divisors (see below), whose sum is σ = 31554288. Its totient is φ = 10379400.

The previous prime is 20897483. The next prime is 20897497. The reversal of 20897494 is 49479802.

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

It is a self number, because there is not a number n which added to its sum of digits gives 20897494.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20897497) 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 3 ways as a sum of consecutive naturals, for example, 34297 + ... + 34900.

It is an arithmetic number, because the mean of its divisors is an integer number (3944286).

Almost surely, 2^20897494 is an apocalyptic number.

20897494 is a deficient number, since it is larger than the sum of its proper divisors (10656794).

20897494 is a wasteful number, since it uses less digits than its factorization.

20897494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69350.

The product of its (nonzero) digits is 145152, while the sum is 43.

The square root of 20897494 is about 4571.3776916811. The cubic root of 20897494 is about 275.4427863972.

The spelling of 20897494 in words is "twenty million, eight hundred ninety-seven thousand, four hundred ninety-four".