1379821261 has 16 divisors (see below), whose sum is σ = 1700019328. Its totient is φ = 1090584000.

The previous prime is 1379821237. The next prime is 1379821273. The reversal of 1379821261 is 1621289731.

It is a cyclic number.

It is not a de Polignac number, because 1379821261 - 2⁵ = 1379821229 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1379821361) 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 15 ways as a sum of consecutive naturals, for example, 85486 + ... + 100336.

It is an arithmetic number, because the mean of its divisors is an integer number (106251208).

Almost surely, 2^1379821261 is an apocalyptic number.

It is an amenable number.

1379821261 is a deficient number, since it is larger than the sum of its proper divisors (320198067).

1379821261 is a wasteful number, since it uses less digits than its factorization.

1379821261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15892.

The product of its digits is 36288, while the sum is 40.

The square root of 1379821261 is about 37145.9454180399. The cubic root of 1379821261 is about 1113.2882126307.

The spelling of 1379821261 in words is "one billion, three hundred seventy-nine million, eight hundred twenty-one thousand, two hundred sixty-one".