121555363642 has 16 divisors (see below), whose sum is σ = 191948160960. Its totient is φ = 57573264672.

The previous prime is 121555363637. The next prime is 121555363649. The reversal of 121555363642 is 246363555121.

It is not an unprimeable number, because it can be changed into a prime (121555363649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 255198 + ... + 555190.

It is an arithmetic number, because the mean of its divisors is an integer number (11996760060).

Almost surely, 2^121555363642 is an apocalyptic number.

121555363642 is a deficient number, since it is larger than the sum of its proper divisors (70392797318).

121555363642 is a wasteful number, since it uses less digits than its factorization.

121555363642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310677.

The product of its digits is 648000, while the sum is 43.

The spelling of 121555363642 in words is "one hundred twenty-one billion, five hundred fifty-five million, three hundred sixty-three thousand, six hundred forty-two".