21361772 has 6 divisors (see below), whose sum is σ = 37383108. Its totient is φ = 10680884.

The previous prime is 21361763. The next prime is 21361787. The reversal of 21361772 is 27716312.

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, 2670218 + ... + 2670225.

It is an arithmetic number, because the mean of its divisors is an integer number (6230518).

Almost surely, 2^21361772 is an apocalyptic number.

It is an amenable number.

21361772 is a deficient number, since it is larger than the sum of its proper divisors (16021336).

21361772 is a wasteful number, since it uses less digits than its factorization.

21361772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5340447 (or 5340445 counting only the distinct ones).

The product of its digits is 3528, while the sum is 29.

The square root of 21361772 is about 4621.8797041896. The cubic root of 21361772 is about 277.4676942074.

The spelling of 21361772 in words is "twenty-one million, three hundred sixty-one thousand, seven hundred seventy-two".