21032091 has 12 divisors (see below), whose sum is σ = 30765280. Its totient is φ = 13843440.

The previous prime is 21032087. The next prime is 21032119. The reversal of 21032091 is 19023012.

It is a happy number.

It is not a de Polignac number, because 21032091 - 2² = 21032087 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21032491) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14080 + ... + 15501.

Almost surely, 2^21032091 is an apocalyptic number.

21032091 is a deficient number, since it is larger than the sum of its proper divisors (9733189).

21032091 is a wasteful number, since it uses less digits than its factorization.

21032091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29666 (or 29663 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 21032091 is about 4586.0757734691. The cubic root of 21032091 is about 276.0328804558.

The spelling of 21032091 in words is "twenty-one million, thirty-two thousand, ninety-one".