21770044 has 6 divisors (see below), whose sum is σ = 38097584. Its totient is φ = 10885020.

The previous prime is 21770033. The next prime is 21770059. The reversal of 21770044 is 44007712.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2721252 + ... + 2721259.

Almost surely, 2^21770044 is an apocalyptic number.

It is an amenable number.

21770044 is a deficient number, since it is larger than the sum of its proper divisors (16327540).

21770044 is a wasteful number, since it uses less digits than its factorization.

21770044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5442515 (or 5442513 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 25.

The square root of 21770044 is about 4665.8379740407. The cubic root of 21770044 is about 279.2242301831.

Adding to 21770044 its reverse (44007712), we get a palindrome (65777756).

The spelling of 21770044 in words is "twenty-one million, seven hundred seventy thousand, forty-four".