21452445 has 120 divisors (see below), whose sum is σ = 47672064. Its totient is φ = 9180864.

The previous prime is 21452443. The next prime is 21452461. The reversal of 21452445 is 54425412.

21452445 is a `hidden beast` number, since 214 + 5 + 2 + 445 = 666.

It is not a de Polignac number, because 21452445 - 2¹ = 21452443 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21452443) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 456412 + ... + 456458.

Almost surely, 2^21452445 is an apocalyptic number.

It is an amenable number.

21452445 is an abundant number, since it is smaller than the sum of its proper divisors (26219619).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21452445 is a wasteful number, since it uses less digits than its factorization.

21452445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101 (or 85 counting only the distinct ones).

The product of its digits is 6400, while the sum is 27.

The square root of 21452445 is about 4631.6784214796. The cubic root of 21452445 is about 277.8597234085.

Adding to 21452445 its reverse (54425412), we get a palindrome (75877857).

The spelling of 21452445 in words is "twenty-one million, four hundred fifty-two thousand, four hundred forty-five".