1217152372057 has 4 divisors (see below), whose sum is σ = 1217159190756. Its totient is φ = 1217145553360.

The previous prime is 1217152372043. The next prime is 1217152372081. The reversal of 1217152372057 is 7502732517121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 577502724096 + 639649647961 = 759936^2 + 799781^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1217152372057 is a prime.

It is a super-2 number, since 2×1217152372057² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1217152372357) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3134194 + ... + 3501067.

It is an arithmetic number, because the mean of its divisors is an integer number (304289797689).

Almost surely, 2^{1217152372057} is an apocalyptic number.

It is an amenable number.

1217152372057 is a deficient number, since it is larger than the sum of its proper divisors (6818699).

1217152372057 is an equidigital number, since it uses as much as digits as its factorization.

1217152372057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6818698.

The product of its (nonzero) digits is 205800, while the sum is 43.

Adding to 1217152372057 its reverse (7502732517121), we get a palindrome (8719884889178).

The spelling of 1217152372057 in words is "one trillion, two hundred seventeen billion, one hundred fifty-two million, three hundred seventy-two thousand, fifty-seven".