21209826270 has 32 divisors (see below), whose sum is σ = 51738072480. Its totient is φ = 5563232640.

The previous prime is 21209826247. The next prime is 21209826283. The reversal of 21209826270 is 7262890212.

It is a super-2 number, since 2×21209826270² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5793205 + ... + 5796864.

It is an arithmetic number, because the mean of its divisors is an integer number (1616814765).

Almost surely, 2^21209826270 is an apocalyptic number.

21209826270 is an abundant number, since it is smaller than the sum of its proper divisors (30528246210).

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

21209826270 is a wasteful number, since it uses less digits than its factorization.

21209826270 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11590140.

The product of its (nonzero) digits is 48384, while the sum is 39.

The spelling of 21209826270 in words is "twenty-one billion, two hundred nine million, eight hundred twenty-six thousand, two hundred seventy".