1787145949 has 2 divisors, whose sum is σ = 1787145950. Its totient is φ = 1787145948.

The previous prime is 1787145937. The next prime is 1787145959. The reversal of 1787145949 is 9495417871.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1405725049 + 381420900 = 37493^2 + 19530^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1787145949 is a prime.

It is a super-2 number, since 2×1787145949² = 6387781286054221202, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1787145949.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1787145959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 893572974 + 893572975.

It is an arithmetic number, because the mean of its divisors is an integer number (893572975).

Almost surely, 2^1787145949 is an apocalyptic number.

It is an amenable number.

1787145949 is a deficient number, since it is larger than the sum of its proper divisors (1).

1787145949 is an equidigital number, since it uses as much as digits as its factorization.

1787145949 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2540160, while the sum is 55.

The square root of 1787145949 is about 42274.6490109616. The cubic root of 1787145949 is about 1213.5378888624.

The spelling of 1787145949 in words is "one billion, seven hundred eighty-seven million, one hundred forty-five thousand, nine hundred forty-nine".