21266772 has 48 divisors (see below), whose sum is σ = 51004800. Its totient is φ = 6894720.

The previous prime is 21266771. The next prime is 21266783. The reversal of 21266772 is 27766212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21266771) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 92754 + ... + 92982.

It is an arithmetic number, because the mean of its divisors is an integer number (1062600).

Almost surely, 2^21266772 is an apocalyptic number.

It is an amenable number.

21266772 is an abundant number, since it is smaller than the sum of its proper divisors (29738028).

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

21266772 is a wasteful number, since it uses less digits than its factorization.

21266772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 416 (or 414 counting only the distinct ones).

The product of its digits is 14112, while the sum is 33.

The square root of 21266772 is about 4611.5910486512. The cubic root of 21266772 is about 277.0557651632.

The spelling of 21266772 in words is "twenty-one million, two hundred sixty-six thousand, seven hundred seventy-two".