21434501 has 16 divisors (see below), whose sum is σ = 25075008. Its totient is φ = 18105600.

The previous prime is 21434471. The next prime is 21434531. The reversal of 21434501 is 10543412.

It is an interprime number because it is at equal distance from previous prime (21434471) and next prime (21434531).

It is a cyclic number.

It is not a de Polignac number, because 21434501 - 2⁶ = 21434437 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21434531) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14831 + ... + 16211.

It is an arithmetic number, because the mean of its divisors is an integer number (1567188).

Almost surely, 2^21434501 is an apocalyptic number.

It is an amenable number.

21434501 is a deficient number, since it is larger than the sum of its proper divisors (3640507).

21434501 is a wasteful number, since it uses less digits than its factorization.

21434501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1492.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 21434501 is about 4629.7409214771. The cubic root of 21434501 is about 277.7822294338.

Adding to 21434501 its reverse (10543412), we get a palindrome (31977913).

The spelling of 21434501 in words is "twenty-one million, four hundred thirty-four thousand, five hundred one".