21098667 has 4 divisors (see below), whose sum is σ = 28131560. Its totient is φ = 14065776.

The previous prime is 21098663. The next prime is 21098669. The reversal of 21098667 is 76689012.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21098667 - 2² = 21098663 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21098663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3516442 + ... + 3516447.

It is an arithmetic number, because the mean of its divisors is an integer number (7032890).

Almost surely, 2^21098667 is an apocalyptic number.

21098667 is a deficient number, since it is larger than the sum of its proper divisors (7032893).

21098667 is an equidigital number, since it uses as much as digits as its factorization.

21098667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7032892.

The product of its (nonzero) digits is 36288, while the sum is 39.

The square root of 21098667 is about 4593.3285316859. The cubic root of 21098667 is about 276.3238296283.

The spelling of 21098667 in words is "twenty-one million, ninety-eight thousand, six hundred sixty-seven".