20464421 has 2 divisors, whose sum is σ = 20464422. Its totient is φ = 20464420.

The previous prime is 20464417. The next prime is 20464439. The reversal of 20464421 is 12446402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19492225 + 972196 = 4415^2 + 986^2 .

It is a cyclic number.

It is not a de Polignac number, because 20464421 - 2² = 20464417 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20464471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10232210 + 10232211.

It is an arithmetic number, because the mean of its divisors is an integer number (10232211).

Almost surely, 2^20464421 is an apocalyptic number.

It is an amenable number.

20464421 is a deficient number, since it is larger than the sum of its proper divisors (1).

20464421 is an equidigital number, since it uses as much as digits as its factorization.

20464421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536, while the sum is 23.

The square root of 20464421 is about 4523.7618195480. The cubic root of 20464421 is about 273.5267596115.

The spelling of 20464421 in words is "twenty million, four hundred sixty-four thousand, four hundred twenty-one".