1225616516550 has 144 divisors (see below), whose sum is σ = 3513612532560. Its totient is φ = 305387781120.

The previous prime is 1225616516539. The next prime is 1225616516557. The reversal of 1225616516550 is 556156165221.

It is a happy number.

1225616516550 is a `hidden beast` number, since 1 + 2 + 25 + 6 + 1 + 65 + 16 + 550 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 1225616516496 and 1225616516505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1225616516557) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 357679 + ... + 1605978.

Almost surely, 2^{1225616516550} is an apocalyptic number.

1225616516550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1225616516550 is an abundant number, since it is smaller than the sum of its proper divisors (2287996016010).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1225616516550 is a wasteful number, since it uses less digits than its factorization.

1225616516550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1963767 (or 1963759 counting only the distinct ones).

The product of its (nonzero) digits is 540000, while the sum is 45.

The spelling of 1225616516550 in words is "one trillion, two hundred twenty-five billion, six hundred sixteen million, five hundred sixteen thousand, five hundred fifty".