21060004 has 18 divisors (see below), whose sum is σ = 42872550. Its totient is φ = 9025632.

The previous prime is 21060001. The next prime is 21060023. The reversal of 21060004 is 40006012.

It can be written as a sum of positive squares in only one way, i.e., 11573604 + 9486400 = 3402^2 + 3080^2 .

It is not an unprimeable number, because it can be changed into a prime (21060001) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 53529 + ... + 53920.

Almost surely, 2^21060004 is an apocalyptic number.

It is an amenable number.

21060004 is an abundant number, since it is smaller than the sum of its proper divisors (21812546).

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

21060004 is a wasteful number, since it uses less digits than its factorization.

21060004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107467 (or 107458 counting only the distinct ones).

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

The square root of 21060004 is about 4589.1179980471. The cubic root of 21060004 is about 276.1549399592.

Adding to 21060004 its reverse (40006012), we get a palindrome (61066016).

The spelling of 21060004 in words is "twenty-one million, sixty thousand, four".