1212153857 has 2 divisors, whose sum is σ = 1212153858. Its totient is φ = 1212153856.

The previous prime is 1212153827. The next prime is 1212153863. The reversal of 1212153857 is 7583512121.

It is a Cunningham number, because it is equal to 34816²+1.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1212153856 + 1 = 34816^2 + 1^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212153857 - 2¹² = 1212149761 is a prime.

It is not a weakly prime, because it can be changed into another prime (1212153827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606076928 + 606076929.

It is an arithmetic number, because the mean of its divisors is an integer number (606076929).

It is a Proth number, since it is equal to 289 ⋅ 2²² + 1 and 289 < 2²².

Almost surely, 2^1212153857 is an apocalyptic number.

It is an amenable number.

1212153857 is a deficient number, since it is larger than the sum of its proper divisors (1).

1212153857 is an equidigital number, since it uses as much as digits as its factorization.

1212153857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16800, while the sum is 35.

The square root of 1212153857 is about 34816.0000143612. Note that the first 4 decimals coincide. The cubic root of 1212153857 is about 1066.2341360377.

Adding to 1212153857 its reverse (7583512121), we get a palindrome (8795665978).

The spelling of 1212153857 in words is "one billion, two hundred twelve million, one hundred fifty-three thousand, eight hundred fifty-seven".