106721009 has 2 divisors, whose sum is σ = 106721010. Its totient is φ = 106721008.

The previous prime is 106720993. The next prime is 106721033. The reversal of 106721009 is 900127601.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 79263409 + 27457600 = 8903^2 + 5240^2 .

It is a cyclic number.

It is not a de Polignac number, because 106721009 - 2⁴ = 106720993 is a prime.

It is a super-2 number, since 2×106721009² = 22778747523956162, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (106723009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 53360504 + 53360505.

It is an arithmetic number, because the mean of its divisors is an integer number (53360505).

Almost surely, 2^106721009 is an apocalyptic number.

It is an amenable number.

106721009 is a deficient number, since it is larger than the sum of its proper divisors (1).

106721009 is an equidigital number, since it uses as much as digits as its factorization.

106721009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 756, while the sum is 26.

The square root of 106721009 is about 10330.5860917956. The cubic root of 106721009 is about 474.3329643764.

The spelling of 106721009 in words is "one hundred six million, seven hundred twenty-one thousand, nine".