21291076 has 12 divisors (see below), whose sum is σ = 37416960. Its totient is φ = 10600520.

The previous prime is 21291029. The next prime is 21291091. The reversal of 21291076 is 67019212.

It is a happy number.

It is a pancake number, because a pancake can be divided into 21291076 parts by 6525 straight cuts.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10180 + ... + 12091.

It is an arithmetic number, because the mean of its divisors is an integer number (3118080).

Almost surely, 2^21291076 is an apocalyptic number.

It is an amenable number.

21291076 is a deficient number, since it is larger than the sum of its proper divisors (16125884).

21291076 is a wasteful number, since it uses less digits than its factorization.

21291076 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22514 (or 22512 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 21291076 is about 4614.2253954483. The cubic root of 21291076 is about 277.1612662060.

The spelling of 21291076 in words is "twenty-one million, two hundred ninety-one thousand, seventy-six".