1390261669 has 2 divisors, whose sum is σ = 1390261670. Its totient is φ = 1390261668.

The previous prime is 1390261627. The next prime is 1390261699. The reversal of 1390261669 is 9661620931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1206659169 + 183602500 = 34737^2 + 13550^2 .

It is a cyclic number.

It is not a de Polignac number, because 1390261669 - 2⁷ = 1390261541 is a prime.

It is a super-2 number, since 2×1390261669² = 3865655016581331122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1390261699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 695130834 + 695130835.

It is an arithmetic number, because the mean of its divisors is an integer number (695130835).

Almost surely, 2^1390261669 is an apocalyptic number.

It is an amenable number.

1390261669 is a deficient number, since it is larger than the sum of its proper divisors (1).

1390261669 is an equidigital number, since it uses as much as digits as its factorization.

1390261669 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 104976, while the sum is 43.

The square root of 1390261669 is about 37286.2128540832. The cubic root of 1390261669 is about 1116.0890561225.

The spelling of 1390261669 in words is "one billion, three hundred ninety million, two hundred sixty-one thousand, six hundred sixty-nine".