1379781421 has 8 divisors (see below), whose sum is σ = 1463824440. Its totient is φ = 1296058368.

The previous prime is 1379781413. The next prime is 1379781433. The reversal of 1379781421 is 1241879731.

It can be written as a sum of positive squares in 4 ways, for example, as 1052678025 + 327103396 = 32445^2 + 18086^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1379781421 - 2³ = 1379781413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1379781461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71076 + ... + 88381.

It is an arithmetic number, because the mean of its divisors is an integer number (182978055).

Almost surely, 2^1379781421 is an apocalyptic number.

It is an amenable number.

1379781421 is a deficient number, since it is larger than the sum of its proper divisors (84043019).

1379781421 is a wasteful number, since it uses less digits than its factorization.

1379781421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159983.

The product of its digits is 84672, while the sum is 43.

The square root of 1379781421 is about 37145.4091510647. The cubic root of 1379781421 is about 1113.2774977576.

The spelling of 1379781421 in words is "one billion, three hundred seventy-nine million, seven hundred eighty-one thousand, four hundred twenty-one".