20709490 has 16 divisors (see below), whose sum is σ = 37402560. Its totient is φ = 8255920.

The previous prime is 20709473. The next prime is 20709497. The reversal of 20709490 is 9490702.

It is not an unprimeable number, because it can be changed into a prime (20709497) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 220 + ... + 6439.

It is an arithmetic number, because the mean of its divisors is an integer number (2337660).

Almost surely, 2^20709490 is an apocalyptic number.

20709490 is a deficient number, since it is larger than the sum of its proper divisors (16693070).

20709490 is a wasteful number, since it uses less digits than its factorization.

20709490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6977.

The product of its (nonzero) digits is 4536, while the sum is 31.

The square root of 20709490 is about 4550.7680670410. The cubic root of 20709490 is about 274.6142912224.

The spelling of 20709490 in words is "twenty million, seven hundred nine thousand, four hundred ninety".