20870824 has 48 divisors (see below), whose sum is σ = 43480800. Its totient is φ = 9382464.

The previous prime is 20870813. The next prime is 20870869. The reversal of 20870824 is 42807802.

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, 57957 + ... + 58315.

It is an arithmetic number, because the mean of its divisors is an integer number (905850).

Almost surely, 2^20870824 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 20870824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21740400).

20870824 is an abundant number, since it is smaller than the sum of its proper divisors (22609976).

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

20870824 is a wasteful number, since it uses less digits than its factorization.

20870824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 434 (or 417 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 31.

The square root of 20870824 is about 4568.4596966593. The cubic root of 20870824 is about 275.3255604367.

The spelling of 20870824 in words is "twenty million, eight hundred seventy thousand, eight hundred twenty-four".