1210121099 has 4 divisors (see below), whose sum is σ = 1320132120. Its totient is φ = 1100110080.

The previous prime is 1210121063. The next prime is 1210121113. The reversal of 1210121099 is 9901210121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9901210121 = 11 ⋅900110011.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1210121099 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1210120099) 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, 55005494 + ... + 55005515.

It is an arithmetic number, because the mean of its divisors is an integer number (330033030).

Almost surely, 2^1210121099 is an apocalyptic number.

1210121099 is a deficient number, since it is larger than the sum of its proper divisors (110011021).

1210121099 is a wasteful number, since it uses less digits than its factorization.

1210121099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110011020.

The product of its (nonzero) digits is 324, while the sum is 26.

The square root of 1210121099 is about 34786.7948940399. The cubic root of 1210121099 is about 1065.6377847172.

The spelling of 1210121099 in words is "one billion, two hundred ten million, one hundred twenty-one thousand, ninety-nine".