121210102009 has 2 divisors, whose sum is σ = 121210102010. Its totient is φ = 121210102008.

The previous prime is 121210101977. The next prime is 121210102103. The reversal of 121210102009 is 900201012121.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 89880040000 + 31330062009 = 299800^2 + 177003^2 .

It is a cyclic number.

It is not a de Polignac number, because 121210102009 - 2⁵ = 121210101977 is a prime.

It is not a weakly prime, because it can be changed into another prime (121210102109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60605051004 + 60605051005.

It is an arithmetic number, because the mean of its divisors is an integer number (60605051005).

Almost surely, 2^121210102009 is an apocalyptic number.

It is an amenable number.

121210102009 is a deficient number, since it is larger than the sum of its proper divisors (1).

121210102009 is an equidigital number, since it uses as much as digits as its factorization.

121210102009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 121210102009 in words is "one hundred twenty-one billion, two hundred ten million, one hundred two thousand, nine".