21004262 has 4 divisors (see below), whose sum is σ = 31506396. Its totient is φ = 10502130.

The previous prime is 21004261. The next prime is 21004273. The reversal of 21004262 is 26240012.

It is a semiprime because it is the product of two primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21004262.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21004261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5251064 + ... + 5251067.

It is an arithmetic number, because the mean of its divisors is an integer number (7876599).

Almost surely, 2^21004262 is an apocalyptic number.

21004262 is a deficient number, since it is larger than the sum of its proper divisors (10502134).

21004262 is a wasteful number, since it uses less digits than its factorization.

21004262 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10502133.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 21004262 is about 4583.0406936880. The cubic root of 21004262 is about 275.9110807166.

Adding to 21004262 its reverse (26240012), we get a palindrome (47244274).

The spelling of 21004262 in words is "twenty-one million, four thousand, two hundred sixty-two".