1378146989 has 2 divisors, whose sum is σ = 1378146990. Its totient is φ = 1378146988.

The previous prime is 1378146967. The next prime is 1378147003. The reversal of 1378146989 is 9896418731.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1281282025 + 96864964 = 35795^2 + 9842^2 .

It is an emirp because it is prime and its reverse (9896418731) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1378146989 is a prime.

It is a super-2 number, since 2×1378146989² = 3798578246579532242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1378146929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 689073494 + 689073495.

It is an arithmetic number, because the mean of its divisors is an integer number (689073495).

Almost surely, 2^1378146989 is an apocalyptic number.

It is an amenable number.

1378146989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1378146989 is an equidigital number, since it uses as much as digits as its factorization.

1378146989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2612736, while the sum is 56.

The square root of 1378146989 is about 37123.4021743697. The cubic root of 1378146989 is about 1112.8377432482.

The spelling of 1378146989 in words is "one billion, three hundred seventy-eight million, one hundred forty-six thousand, nine hundred eighty-nine".