121020251 has 4 divisors (see below), whose sum is σ = 132022104. Its totient is φ = 110018400.

The previous prime is 121020241. The next prime is 121020257. The reversal of 121020251 is 152020121.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121020251 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121020257) 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, 5500910 + ... + 5500931.

It is an arithmetic number, because the mean of its divisors is an integer number (33005526).

Almost surely, 2^121020251 is an apocalyptic number.

121020251 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

121020251 is a deficient number, since it is larger than the sum of its proper divisors (11001853).

121020251 is a wasteful number, since it uses less digits than its factorization.

121020251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11001852.

The product of its (nonzero) digits is 40, while the sum is 14.

The square root of 121020251 is about 11000.9204614887. The cubic root of 121020251 is about 494.6363359583.

Adding to 121020251 its reverse (152020121), we get a palindrome (273040372).

The spelling of 121020251 in words is "one hundred twenty-one million, twenty thousand, two hundred fifty-one".