109517921 has 2 divisors, whose sum is σ = 109517922. Its totient is φ = 109517920.

The previous prime is 109517899. The next prime is 109517951. The reversal of 109517921 is 129715901.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 86285521 + 23232400 = 9289^2 + 4820^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-109517921 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (109517951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54758960 + 54758961.

It is an arithmetic number, because the mean of its divisors is an integer number (54758961).

Almost surely, 2^109517921 is an apocalyptic number.

It is an amenable number.

109517921 is a deficient number, since it is larger than the sum of its proper divisors (1).

109517921 is an equidigital number, since it uses as much as digits as its factorization.

109517921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5670, while the sum is 35.

The square root of 109517921 is about 10465.0810316977. The cubic root of 109517921 is about 478.4410082952.

The spelling of 109517921 in words is "one hundred nine million, five hundred seventeen thousand, nine hundred twenty-one".