1504978781 has 2 divisors, whose sum is σ = 1504978782. Its totient is φ = 1504978780.

The previous prime is 1504978691. The next prime is 1504978879. The reversal of 1504978781 is 1878794051.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1289887225 + 215091556 = 35915^2 + 14666^2 .

It is an emirp because it is prime and its reverse (1878794051) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1504978781 - 2³⁰ = 431236957 is a prime.

It is a super-2 number, since 2×1504978781² = 4529922262520491922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1504918781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 752489390 + 752489391.

It is an arithmetic number, because the mean of its divisors is an integer number (752489391).

Almost surely, 2^1504978781 is an apocalyptic number.

It is an amenable number.

1504978781 is a deficient number, since it is larger than the sum of its proper divisors (1).

1504978781 is an equidigital number, since it uses as much as digits as its factorization.

1504978781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 564480, while the sum is 50.

The square root of 1504978781 is about 38794.0560008876. The cubic root of 1504978781 is about 1145.9793508783.

The spelling of 1504978781 in words is "one billion, five hundred four million, nine hundred seventy-eight thousand, seven hundred eighty-one".