20297990 has 8 divisors (see below), whose sum is σ = 36536400. Its totient is φ = 8119192.

The previous prime is 20297971. The next prime is 20298001. The reversal of 20297990 is 9979202.

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

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, 1014890 + ... + 1014909.

It is an arithmetic number, because the mean of its divisors is an integer number (4567050).

Almost surely, 2^20297990 is an apocalyptic number.

20297990 is a deficient number, since it is larger than the sum of its proper divisors (16238410).

20297990 is a wasteful number, since it uses less digits than its factorization.

20297990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2029806.

The product of its (nonzero) digits is 20412, while the sum is 38.

The square root of 20297990 is about 4505.3290667830. The cubic root of 20297990 is about 272.7832366298.

The spelling of 20297990 in words is "twenty million, two hundred ninety-seven thousand, nine hundred ninety".