20861698 has 48 divisors (see below), whose sum is σ = 38368512. Its totient is φ = 8424000.

The previous prime is 20861663. The next prime is 20861699. The reversal of 20861698 is 89616802.

It is a self number, because there is not a number n which added to its sum of digits gives 20861698.

It is not an unprimeable number, because it can be changed into a prime (20861699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 115168 + ... + 115348.

It is an arithmetic number, because the mean of its divisors is an integer number (799344).

Almost surely, 2^20861698 is an apocalyptic number.

20861698 is a deficient number, since it is larger than the sum of its proper divisors (17506814).

20861698 is a wasteful number, since it uses less digits than its factorization.

20861698 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 251 (or 238 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 40.

The square root of 20861698 is about 4567.4607825355. The cubic root of 20861698 is about 275.2854248647.

The spelling of 20861698 in words is "twenty million, eight hundred sixty-one thousand, six hundred ninety-eight".