21266958 has 16 divisors (see below), whose sum is σ = 43073280. Its totient is φ = 6999096.

The previous prime is 21266953. The next prime is 21266977. The reversal of 21266958 is 85966212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21266951) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21960 + ... + 22907.

It is an arithmetic number, because the mean of its divisors is an integer number (2692080).

Almost surely, 2^21266958 is an apocalyptic number.

21266958 is an abundant number, since it is smaller than the sum of its proper divisors (21806322).

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

21266958 is a wasteful number, since it uses less digits than its factorization.

21266958 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44951.

The product of its digits is 51840, while the sum is 39.

The square root of 21266958 is about 4611.6112151828. The cubic root of 21266958 is about 277.0565728743.

The spelling of 21266958 in words is "twenty-one million, two hundred sixty-six thousand, nine hundred fifty-eight".