21414645 has 128 divisors (see below), whose sum is σ = 48660480. Its totient is φ = 8709120.

The previous prime is 21414641. The next prime is 21414649. The reversal of 21414645 is 54641412.

21414645 is a `hidden beast` number, since 2 + 1 + 4 + 14 + 645 = 666.

It is an interprime number because it is at equal distance from previous prime (21414641) and next prime (21414649).

It is not a de Polignac number, because 21414645 - 2² = 21414641 is a prime.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21414641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 497994 + ... + 498036.

It is an arithmetic number, because the mean of its divisors is an integer number (380160).

Almost surely, 2^21414645 is an apocalyptic number.

It is an amenable number.

21414645 is an abundant number, since it is smaller than the sum of its proper divisors (27245835).

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

21414645 is a wasteful number, since it uses less digits than its factorization.

21414645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112 (or 106 counting only the distinct ones).

The product of its digits is 3840, while the sum is 27.

The square root of 21414645 is about 4627.5960281770. The cubic root of 21414645 is about 277.6964277633.

It can be divided in two parts, 2141 and 4645, that added together give a triangular number (6786 = T₁₁₆).

The spelling of 21414645 in words is "twenty-one million, four hundred fourteen thousand, six hundred forty-five".