121720502 has 4 divisors (see below), whose sum is σ = 182580756. Its totient is φ = 60860250.

The previous prime is 121720499. The next prime is 121720507. The reversal of 121720502 is 205027121.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121720507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30430124 + ... + 30430127.

It is an arithmetic number, because the mean of its divisors is an integer number (45645189).

Almost surely, 2^121720502 is an apocalyptic number.

121720502 is a deficient number, since it is larger than the sum of its proper divisors (60860254).

121720502 is an equidigital number, since it uses as much as digits as its factorization.

121720502 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60860253.

The product of its (nonzero) digits is 280, while the sum is 20.

The square root of 121720502 is about 11032.7014824113. The cubic root of 121720502 is about 495.5885283043.

Adding to 121720502 its reverse (205027121), we get a palindrome (326747623).

The spelling of 121720502 in words is "one hundred twenty-one million, seven hundred twenty thousand, five hundred two".