1381577906509 has 2 divisors, whose sum is σ = 1381577906510. Its totient is φ = 1381577906508.

The previous prime is 1381577906459. The next prime is 1381577906519. The reversal of 1381577906509 is 9056097751831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1259382217284 + 122195689225 = 1122222^2 + 349565^2 .

It is a cyclic number.

It is not a de Polignac number, because 1381577906509 - 2⁷ = 1381577906381 is a prime.

It is a super-2 number, since 2×1381577906509² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1381577906519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 690788953254 + 690788953255.

It is an arithmetic number, because the mean of its divisors is an integer number (690788953255).

Almost surely, 2^{1381577906509} is an apocalyptic number.

It is an amenable number.

1381577906509 is a deficient number, since it is larger than the sum of its proper divisors (1).

1381577906509 is an equidigital number, since it uses as much as digits as its factorization.

1381577906509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14288400, while the sum is 61.

The spelling of 1381577906509 in words is "one trillion, three hundred eighty-one billion, five hundred seventy-seven million, nine hundred six thousand, five hundred nine".