20918470 has 8 divisors (see below), whose sum is σ = 37653264. Its totient is φ = 8367384.

The previous prime is 20918467. The next prime is 20918479. The reversal of 20918470 is 7481902.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20918479) 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 3 ways as a sum of consecutive naturals, for example, 1045914 + ... + 1045933.

It is an arithmetic number, because the mean of its divisors is an integer number (4706658).

Almost surely, 2^20918470 is an apocalyptic number.

20918470 is a deficient number, since it is larger than the sum of its proper divisors (16734794).

20918470 is a wasteful number, since it uses less digits than its factorization.

20918470 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2091854.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 20918470 is about 4573.6713917814. The cubic root of 20918470 is about 275.5349147617.

The spelling of 20918470 in words is "twenty million, nine hundred eighteen thousand, four hundred seventy".