121555363646 has 16 divisors (see below), whose sum is σ = 186611040000. Its totient is φ = 59352254808.

The previous prime is 121555363637. The next prime is 121555363649. The reversal of 121555363646 is 646363555121.

It is a super-2 number, since 2×121555363646² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 121555363646.

It is a congruent number.

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

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 293105 + ... + 573603.

It is an arithmetic number, because the mean of its divisors is an integer number (11663190000).

Almost surely, 2^121555363646 is an apocalyptic number.

121555363646 is a deficient number, since it is larger than the sum of its proper divisors (65055676354).

121555363646 is a wasteful number, since it uses less digits than its factorization.

121555363646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285583.

The product of its digits is 1944000, while the sum is 47.

The spelling of 121555363646 in words is "one hundred twenty-one billion, five hundred fifty-five million, three hundred sixty-three thousand, six hundred forty-six".