21440502 has 24 divisors (see below), whose sum is σ = 49187736. Its totient is φ = 6726336.

The previous prime is 21440491. The next prime is 21440527. The reversal of 21440502 is 20504412.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34728 + ... + 35339.

It is an arithmetic number, because the mean of its divisors is an integer number (2049489).

Almost surely, 2^21440502 is an apocalyptic number.

21440502 is an abundant number, since it is smaller than the sum of its proper divisors (27747234).

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

21440502 is a wasteful number, since it uses less digits than its factorization.

21440502 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70092 (or 70089 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 21440502 is about 4630.3889685425. The cubic root of 21440502 is about 277.8081505041.

Adding to 21440502 its reverse (20504412), we get a palindrome (41944914).

The spelling of 21440502 in words is "twenty-one million, four hundred forty thousand, five hundred two".