20406897 has 64 divisors (see below), whose sum is σ = 36945920. Its totient is φ = 11022480.

The previous prime is 20406833. The next prime is 20406917. The reversal of 20406897 is 79860402.

It is not a de Polignac number, because 20406897 - 2⁶ = 20406833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20406697) 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 63 ways as a sum of consecutive naturals, for example, 474558 + ... + 474600.

It is an arithmetic number, because the mean of its divisors is an integer number (577280).

Almost surely, 2^20406897 is an apocalyptic number.

20406897 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

20406897 is a deficient number, since it is larger than the sum of its proper divisors (16539023).

20406897 is an frugal number, since it uses more digits than its factorization.

20406897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102 (or 84 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 20406897 is about 4517.3993624651. The cubic root of 20406897 is about 273.2702311534.

The spelling of 20406897 in words is "twenty million, four hundred six thousand, eight hundred ninety-seven".