20699136 has 72 divisors (see below), whose sum is σ = 59836140. Its totient is φ = 6893568.

The previous prime is 20699131. The next prime is 20699141. The reversal of 20699136 is 63199602.

It is an interprime number because it is at equal distance from previous prime (20699131) and next prime (20699141).

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-2 number, since 2×20699136² = 856908462292992, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 20699136.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20699131) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 17871 + ... + 18993.

Almost surely, 2^20699136 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 20699136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29918070).

20699136 is an abundant number, since it is smaller than the sum of its proper divisors (39137004).

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

20699136 is a wasteful number, since it uses less digits than its factorization.

20699136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1151 (or 1128 counting only the distinct ones).

The product of its (nonzero) digits is 17496, while the sum is 36.

The square root of 20699136 is about 4549.6303146519. The cubic root of 20699136 is about 274.5685178377.

The spelling of 20699136 in words is "twenty million, six hundred ninety-nine thousand, one hundred thirty-six".