1655511397 has 2 divisors, whose sum is σ = 1655511398. Its totient is φ = 1655511396.

The previous prime is 1655511379. The next prime is 1655511419. The reversal of 1655511397 is 7931155561.

Together with previous prime (1655511379) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1655350596 + 160801 = 40686^2 + 401^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1655511397 is a prime.

It is a super-4 number, since 4×1655511397⁴ (a number of 38 digits) contains 4444 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1655511307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 827755698 + 827755699.

It is an arithmetic number, because the mean of its divisors is an integer number (827755699).

Almost surely, 2^1655511397 is an apocalyptic number.

It is an amenable number.

1655511397 is a deficient number, since it is larger than the sum of its proper divisors (1).

1655511397 is an equidigital number, since it uses as much as digits as its factorization.

1655511397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 141750, while the sum is 43.

The square root of 1655511397 is about 40687.9760740197. The cubic root of 1655511397 is about 1182.9799709218.

The spelling of 1655511397 in words is "one billion, six hundred fifty-five million, five hundred eleven thousand, three hundred ninety-seven".