20718401 has 4 divisors (see below), whose sum is σ = 22601904. Its totient is φ = 18834900.

The previous prime is 20718353. The next prime is 20718403. The reversal of 20718401 is 10481702.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20718401 - 2⁶ = 20718337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20718403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 941735 + ... + 941756.

It is an arithmetic number, because the mean of its divisors is an integer number (5650476).

Almost surely, 2^20718401 is an apocalyptic number.

It is an amenable number.

20718401 is a deficient number, since it is larger than the sum of its proper divisors (1883503).

20718401 is a wasteful number, since it uses less digits than its factorization.

20718401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1883502.

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 20718401 is about 4551.7470272413. The cubic root of 20718401 is about 274.6536731202.

The spelling of 20718401 in words is "twenty million, seven hundred eighteen thousand, four hundred one".