21210703 has 2 divisors, whose sum is σ = 21210704. Its totient is φ = 21210702.

The previous prime is 21210697. The next prime is 21210719. The reversal of 21210703 is 30701212.

It is a happy number.

It is an a-pointer prime, because the next prime (21210719) can be obtained adding 21210703 to its sum of digits (16).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21210703 - 2¹⁷ = 21079631 is a prime.

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

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21210743) 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 as a sum of consecutive naturals, namely, 10605351 + 10605352.

It is an arithmetic number, because the mean of its divisors is an integer number (10605352).

Almost surely, 2^21210703 is an apocalyptic number.

21210703 is a deficient number, since it is larger than the sum of its proper divisors (1).

21210703 is an equidigital number, since it uses as much as digits as its factorization.

21210703 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 84, while the sum is 16.

The square root of 21210703 is about 4605.5078981585. The cubic root of 21210703 is about 276.8120686973.

Adding to 21210703 its reverse (30701212), we get a palindrome (51911915).

The spelling of 21210703 in words is "twenty-one million, two hundred ten thousand, seven hundred three".