21070196 has 36 divisors (see below), whose sum is σ = 43192548. Its totient is φ = 8967168.

The previous prime is 21070121. The next prime is 21070201. The reversal of 21070196 is 69107012.

It can be written as a sum of positive squares in 2 ways, for example, as 3312400 + 17757796 = 1820^2 + 4214^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 37550 + ... + 38106.

It is an arithmetic number, because the mean of its divisors is an integer number (1199793).

Almost surely, 2^21070196 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21070196, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21596274).

21070196 is an abundant number, since it is smaller than the sum of its proper divisors (22122352).

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

21070196 is a wasteful number, since it uses less digits than its factorization.

21070196 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 768 (or 759 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 26.

The square root of 21070196 is about 4590.2283167616. The cubic root of 21070196 is about 276.1994812174.

The spelling of 21070196 in words is "twenty-one million, seventy thousand, one hundred ninety-six".