20218401 has 12 divisors (see below), whose sum is σ = 33376512. Its totient is φ = 11553336.

The previous prime is 20218381. The next prime is 20218411. The reversal of 20218401 is 10481202.

It is not a de Polignac number, because 20218401 - 2¹¹ = 20216353 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20218411) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 160401 + ... + 160526.

It is an arithmetic number, because the mean of its divisors is an integer number (2781376).

Almost surely, 2^20218401 is an apocalyptic number.

20218401 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20218401 is a deficient number, since it is larger than the sum of its proper divisors (13158111).

20218401 is a wasteful number, since it uses less digits than its factorization.

20218401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320940 (or 320937 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 20218401 is about 4496.4876292502. The cubic root of 20218401 is about 272.4262393297.

Adding to 20218401 its reverse (10481202), we get a palindrome (30699603).

The spelling of 20218401 in words is "twenty million, two hundred eighteen thousand, four hundred one".