21476861 has 16 divisors (see below), whose sum is σ = 25251840. Its totient is φ = 17886960.

The previous prime is 21476837. The next prime is 21476879. The reversal of 21476861 is 16867412.

It is not a de Polignac number, because 21476861 - 2¹⁰ = 21475837 is a prime.

It is a super-2 number, since 2×21476861² = 922511116826642, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21476801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38990 + ... + 39536.

It is an arithmetic number, because the mean of its divisors is an integer number (1578240).

Almost surely, 2^21476861 is an apocalyptic number.

It is an amenable number.

21476861 is a deficient number, since it is larger than the sum of its proper divisors (3774979).

21476861 is an equidigital number, since it uses as much as digits as its factorization.

21476861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 704.

The product of its digits is 16128, while the sum is 35.

The square root of 21476861 is about 4634.3134335088. The cubic root of 21476861 is about 277.9650983564.

The spelling of 21476861 in words is "twenty-one million, four hundred seventy-six thousand, eight hundred sixty-one".