20823400 has 48 divisors (see below), whose sum is σ = 52145100. Its totient is φ = 7687680.

The previous prime is 20823359. The next prime is 20823409. The reversal of 20823400 is 432802.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 5189284 + 15634116 = 2278^2 + 3954^2 .

It is a super-2 number, since 2×20823400² = 867227975120000, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20823409) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1405 + ... + 6604.

Almost surely, 2^20823400 is an apocalyptic number.

20823400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20823400 is an abundant number, since it is smaller than the sum of its proper divisors (31321700).

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

20823400 is a wasteful number, since it uses less digits than its factorization.

20823400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8038 (or 8029 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 20823400 is about 4563.2663739913. The cubic root of 20823400 is about 275.1168649302.

The spelling of 20823400 in words is "twenty million, eight hundred twenty-three thousand, four hundred".