21136197 has 16 divisors (see below), whose sum is σ = 29034432. Its totient is φ = 13668480.

The previous prime is 21136187. The next prime is 21136207. The reversal of 21136197 is 79163112.

It is an interprime number because it is at equal distance from previous prime (21136187) and next prime (21136207).

It is not a de Polignac number, because 21136197 - 2⁶ = 21136133 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21136127) 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, 27543 + ... + 28299.

It is an arithmetic number, because the mean of its divisors is an integer number (1814652).

Almost surely, 2^21136197 is an apocalyptic number.

It is an amenable number.

21136197 is a deficient number, since it is larger than the sum of its proper divisors (7898235).

21136197 is a wasteful number, since it uses less digits than its factorization.

21136197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1028.

The product of its digits is 2268, while the sum is 30.

The square root of 21136197 is about 4597.4119893697. The cubic root of 21136197 is about 276.4875728397.

The spelling of 21136197 in words is "twenty-one million, one hundred thirty-six thousand, one hundred ninety-seven".