1242445251555 has 96 divisors (see below), whose sum is σ = 2289536720640. Its totient is φ = 621505509120.

The previous prime is 1242445251529. The next prime is 1242445251569. The reversal of 1242445251555 is 5551525442421.

1242445251555 is a `hidden beast` number, since 1 + 2 + 4 + 2 + 4 + 45 + 2 + 51 + 555 = 666.

It is not a de Polignac number, because 1242445251555 - 2⁷ = 1242445251427 is a prime.

It is a super-2 number, since 2×1242445251555² (a number of 25 digits) contains 22 as substring.

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 1242445251555.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 194951349 + ... + 194957721.

It is an arithmetic number, because the mean of its divisors is an integer number (23849340840).

Almost surely, 2^{1242445251555} is an apocalyptic number.

1242445251555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1242445251555 is a deficient number, since it is larger than the sum of its proper divisors (1047091469085).

1242445251555 is a wasteful number, since it uses less digits than its factorization.

1242445251555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8641 (or 8638 counting only the distinct ones).

The product of its digits is 1600000, while the sum is 45.

The spelling of 1242445251555 in words is "one trillion, two hundred forty-two billion, four hundred forty-five million, two hundred fifty-one thousand, five hundred fifty-five".