21423100 has 36 divisors (see below), whose sum is σ = 46714024. Its totient is φ = 8527680.

The previous prime is 21423079. The next prime is 21423107. The reversal of 21423100 is 132412.

It is a super-2 number, since 2×21423100² = 917898427220000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21423107) 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, 27922 + ... + 28678.

Almost surely, 2^21423100 is an apocalyptic number.

21423100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21423100 is an abundant number, since it is smaller than the sum of its proper divisors (25290924).

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

21423100 is a wasteful number, since it uses less digits than its factorization.

21423100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1054 (or 1047 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 21423100 is about 4628.5094793032. The cubic root of 21423100 is about 277.7329699577.

Adding to 21423100 its reverse (132412), we get a palindrome (21555512).

The spelling of 21423100 in words is "twenty-one million, four hundred twenty-three thousand, one hundred".