20452421 has 4 divisors (see below), whose sum is σ = 22311744. Its totient is φ = 18593100.

The previous prime is 20452363. The next prime is 20452427. The reversal of 20452421 is 12425402.

It is a happy number.

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 20452421 - 2⁶ = 20452357 is a prime.

It is a super-2 number, since 2×20452421² = 836603049522482, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20452393 and 20452402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20452427) 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, 929645 + ... + 929666.

It is an arithmetic number, because the mean of its divisors is an integer number (5577936).

Almost surely, 2^20452421 is an apocalyptic number.

It is an amenable number.

20452421 is a deficient number, since it is larger than the sum of its proper divisors (1859323).

20452421 is a wasteful number, since it uses less digits than its factorization.

20452421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1859322.

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 20452421 is about 4522.4352952806. The cubic root of 20452421 is about 273.4732852931.

Adding to 20452421 its reverse (12425402), we get a palindrome (32877823).

It can be divided in two parts, 204 and 52421, that added together give a palindrome (52625).

The spelling of 20452421 in words is "twenty million, four hundred fifty-two thousand, four hundred twenty-one".