21476830 has 16 divisors (see below), whose sum is σ = 38800944. Its totient is φ = 8559040.

The previous prime is 21476827. The next prime is 21476837. The reversal of 21476830 is 3867412.

It is a super-2 number, since 2×21476830² = 922508453697800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21476792 and 21476801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21476837) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1012 + ... + 6631.

It is an arithmetic number, because the mean of its divisors is an integer number (2425059).

It is a vampire number, since it can be written as 2810 ⋅ 7643 (with its own digits).

Almost surely, 2^21476830 is an apocalyptic number.

21476830 is a deficient number, since it is larger than the sum of its proper divisors (17324114).

21476830 is a wasteful number, since it uses less digits than its factorization.

21476830 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7931.

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 21476830 is about 4634.3100888913. The cubic root of 21476830 is about 277.9649646168.

The spelling of 21476830 in words is "twenty-one million, four hundred seventy-six thousand, eight hundred thirty".