20307997 has 8 divisors (see below), whose sum is σ = 21288960. Its totient is φ = 19350240.

The previous prime is 20307983. The next prime is 20308003. The reversal of 20307997 is 79970302.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20307997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20307907) 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, 3997 + ... + 7522.

It is an arithmetic number, because the mean of its divisors is an integer number (2661120).

Almost surely, 2^20307997 is an apocalyptic number.

It is an amenable number.

20307997 is a deficient number, since it is larger than the sum of its proper divisors (980963).

20307997 is a wasteful number, since it uses less digits than its factorization.

20307997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11603.

The product of its (nonzero) digits is 23814, while the sum is 37.

The square root of 20307997 is about 4506.4395036436. The cubic root of 20307997 is about 272.8280570510.

The spelling of 20307997 in words is "twenty million, three hundred seven thousand, nine hundred ninety-seven".