20955901 has 4 divisors (see below), whose sum is σ = 21004732. Its totient is φ = 20907072.

The previous prime is 20955899. The next prime is 20955911. The reversal of 20955901 is 10955902.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10955902 = 2 ⋅5477951.

It can be written as a sum of positive squares in 2 ways, for example, as 9156676 + 11799225 = 3026^2 + 3435^2 .

It is a cyclic number.

It is not a de Polignac number, because 20955901 - 2¹ = 20955899 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 (20955911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23766 + ... + 24631.

It is an arithmetic number, because the mean of its divisors is an integer number (5251183).

Almost surely, 2^20955901 is an apocalyptic number.

It is an amenable number.

20955901 is a deficient number, since it is larger than the sum of its proper divisors (48831).

20955901 is an equidigital number, since it uses as much as digits as its factorization.

20955901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48830.

The product of its (nonzero) digits is 4050, while the sum is 31.

The square root of 20955901 is about 4577.7615708990. The cubic root of 20955901 is about 275.6991619859.

Subtracting from 20955901 its reverse (10955902), we obtain a palindrome (9999999).

The spelling of 20955901 in words is "twenty million, nine hundred fifty-five thousand, nine hundred one".