1391277890 has 16 divisors (see below), whose sum is σ = 2513827008. Its totient is φ = 554394096.

The previous prime is 1391277883. The next prime is 1391277893. The reversal of 1391277890 is 987721931.

It is not an unprimeable number, because it can be changed into a prime (1391277893) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 261872 + ... + 267131.

It is an arithmetic number, because the mean of its divisors is an integer number (157114188).

Almost surely, 2^1391277890 is an apocalyptic number.

1391277890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1391277890 is a deficient number, since it is larger than the sum of its proper divisors (1122549118).

1391277890 is a wasteful number, since it uses less digits than its factorization.

1391277890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 529273.

The product of its (nonzero) digits is 190512, while the sum is 47.

The square root of 1391277890 is about 37299.8376672071. The cubic root of 1391277890 is about 1116.3609274605.

The spelling of 1391277890 in words is "one billion, three hundred ninety-one million, two hundred seventy-seven thousand, eight hundred ninety".