20912390 has 8 divisors (see below), whose sum is σ = 37642320. Its totient is φ = 8364952.

The previous prime is 20912377. The next prime is 20912417. The reversal of 20912390 is 9321902.

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

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1045610 + ... + 1045629.

It is an arithmetic number, because the mean of its divisors is an integer number (4705290).

Almost surely, 2^20912390 is an apocalyptic number.

20912390 is a deficient number, since it is larger than the sum of its proper divisors (16729930).

20912390 is a wasteful number, since it uses less digits than its factorization.

20912390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2091246.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 20912390 is about 4573.0066695775. The cubic root of 20912390 is about 275.5082172289.

The spelling of 20912390 in words is "twenty million, nine hundred twelve thousand, three hundred ninety".