121240402 has 4 divisors (see below), whose sum is σ = 181860606. Its totient is φ = 60620200.

The previous prime is 121240393. The next prime is 121240409. The reversal of 121240402 is 204042121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 204042121 = 19 ⋅10739059.

It can be written as a sum of positive squares in only one way, i.e., 78481881 + 42758521 = 8859^2 + 6539^2 .

It is not an unprimeable number, because it can be changed into a prime (121240409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30310099 + ... + 30310102.

Almost surely, 2^121240402 is an apocalyptic number.

121240402 is a deficient number, since it is larger than the sum of its proper divisors (60620204).

121240402 is an equidigital number, since it uses as much as digits as its factorization.

121240402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60620203.

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 121240402 is about 11010.9219414180. The cubic root of 121240402 is about 494.9360894258.

Adding to 121240402 its reverse (204042121), we get a palindrome (325282523).

It can be divided in two parts, 1212 and 40402, that added together give a palindrome (41614).

The spelling of 121240402 in words is "one hundred twenty-one million, two hundred forty thousand, four hundred two".