20400697 has 8 divisors (see below), whose sum is σ = 22298112. Its totient is φ = 18580800.

The previous prime is 20400689. The next prime is 20400713. The reversal of 20400697 is 79600402.

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

It is a cyclic number.

It is not a de Polignac number, because 20400697 - 2³ = 20400689 is a prime.

It is a Duffinian number.

20400697 is a modest number, since divided by 697 gives 204 as remainder.

It is not an unprimeable number, because it can be changed into a prime (20400637) 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 7 ways as a sum of consecutive naturals, for example, 18829 + ... + 19882.

It is an arithmetic number, because the mean of its divisors is an integer number (2787264).

Almost surely, 2^20400697 is an apocalyptic number.

It is an amenable number.

20400697 is a deficient number, since it is larger than the sum of its proper divisors (1897415).

20400697 is a wasteful number, since it uses less digits than its factorization.

20400697 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38759.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 20400697 is about 4516.7130747923. The cubic root of 20400697 is about 273.2425534676.

The spelling of 20400697 in words is "twenty million, four hundred thousand, six hundred ninety-seven".