1378506261 has 16 divisors (see below), whose sum is σ = 2006222400. Its totient is φ = 834990720.

The previous prime is 1378506211. The next prime is 1378506281. The reversal of 1378506261 is 1626058731.

It is not a de Polignac number, because 1378506261 - 2¹⁵ = 1378473493 is a prime.

It is a super-4 number, since 4×1378506261⁴ (a number of 38 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1378506211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53601 + ... + 75033.

It is an arithmetic number, because the mean of its divisors is an integer number (125388900).

Almost surely, 2^1378506261 is an apocalyptic number.

1378506261 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1378506261 is a deficient number, since it is larger than the sum of its proper divisors (627716139).

1378506261 is a wasteful number, since it uses less digits than its factorization.

1378506261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23396.

The product of its (nonzero) digits is 60480, while the sum is 39.

The square root of 1378506261 is about 37128.2407474418. The cubic root of 1378506261 is about 1112.9344375069.

The spelling of 1378506261 in words is "one billion, three hundred seventy-eight million, five hundred six thousand, two hundred sixty-one".