1212641256465 has 48 divisors (see below), whose sum is σ = 2138263920000. Its totient is φ = 635564103936.

The previous prime is 1212641256427. The next prime is 1212641256467. The reversal of 1212641256465 is 5646521462121.

1212641256465 is a `hidden beast` number, since 1 + 2 + 1 + 2 + 64 + 125 + 6 + 465 = 666.

It is not a de Polignac number, because 1212641256465 - 2¹² = 1212641252369 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 1212641256465.

It is not an unprimeable number, because it can be changed into a prime (1212641256467) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7886197 + ... + 8038493.

It is an arithmetic number, because the mean of its divisors is an integer number (44547165000).

Almost surely, 2^{1212641256465} is an apocalyptic number.

1212641256465 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1212641256465 is a deficient number, since it is larger than the sum of its proper divisors (925622663535).

1212641256465 is a wasteful number, since it uses less digits than its factorization.

1212641256465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155366 (or 155363 counting only the distinct ones).

The product of its digits is 691200, while the sum is 45.

The spelling of 1212641256465 in words is "one trillion, two hundred twelve billion, six hundred forty-one million, two hundred fifty-six thousand, four hundred sixty-five".