21221002196 has 24 divisors (see below), whose sum is σ = 37325481480. Its totient is φ = 10556687232.

The previous prime is 21221002193. The next prime is 21221002217. The reversal of 21221002196 is 69120012212.

It can be written as a sum of positive squares in 4 ways, for example, as 2860752196 + 18360250000 = 53486^2 + 135500^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221002193) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 801506 + ... + 827558.

It is an arithmetic number, because the mean of its divisors is an integer number (1555228395).

Almost surely, 2^21221002196 is an apocalyptic number.

It is an amenable number.

21221002196 is a deficient number, since it is larger than the sum of its proper divisors (16104479284).

21221002196 is a wasteful number, since it uses less digits than its factorization.

21221002196 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27083 (or 27081 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 26.

The spelling of 21221002196 in words is "twenty-one billion, two hundred twenty-one million, two thousand, one hundred ninety-six".