1551965197 has 2 divisors, whose sum is σ = 1551965198. Its totient is φ = 1551965196.

The previous prime is 1551965171. The next prime is 1551965203. The reversal of 1551965197 is 7915691551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1544018436 + 7946761 = 39294^2 + 2819^2 .

It is an emirp because it is prime and its reverse (7915691551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1551965197 - 2⁷ = 1551965069 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1551965197.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1551965147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 775982598 + 775982599.

It is an arithmetic number, because the mean of its divisors is an integer number (775982599).

Almost surely, 2^1551965197 is an apocalyptic number.

It is an amenable number.

1551965197 is a deficient number, since it is larger than the sum of its proper divisors (1).

1551965197 is an equidigital number, since it uses as much as digits as its factorization.

1551965197 is an evil number, because the sum of its binary digits is even.

The product of its digits is 425250, while the sum is 49.

The square root of 1551965197 is about 39394.9894910508. The cubic root of 1551965197 is about 1157.7834200012.

The spelling of 1551965197 in words is "one billion, five hundred fifty-one million, nine hundred sixty-five thousand, one hundred ninety-seven".