1378375451 has 4 divisors (see below), whose sum is σ = 1381487352. Its totient is φ = 1375263552.

The previous prime is 1378375409. The next prime is 1378375477. The reversal of 1378375451 is 1545738731.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1545738731 = 311 ⋅4970221.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1378375451 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1378375651) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1555286 + ... + 1556171.

It is an arithmetic number, because the mean of its divisors is an integer number (345371838).

Almost surely, 2^1378375451 is an apocalyptic number.

1378375451 is a deficient number, since it is larger than the sum of its proper divisors (3111901).

1378375451 is an equidigital number, since it uses as much as digits as its factorization.

1378375451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3111900.

The product of its digits is 352800, while the sum is 44.

The square root of 1378375451 is about 37126.4791085823. The cubic root of 1378375451 is about 1112.8992333241.

The spelling of 1378375451 in words is "one billion, three hundred seventy-eight million, three hundred seventy-five thousand, four hundred fifty-one".