1938378311 has 8 divisors (see below), whose sum is σ = 2005968624. Its totient is φ = 1871588160.

The previous prime is 1938378307. The next prime is 1938378317. The reversal of 1938378311 is 1138738391.

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 1938378311 - 2² = 1938378307 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1938378317) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 195110 + ... + 204803.

It is an arithmetic number, because the mean of its divisors is an integer number (250746078).

Almost surely, 2^1938378311 is an apocalyptic number.

1938378311 is a deficient number, since it is larger than the sum of its proper divisors (67590313).

1938378311 is a wasteful number, since it uses less digits than its factorization.

1938378311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400081.

The product of its digits is 108864, while the sum is 44.

The square root of 1938378311 is about 44027.0179662443. The cubic root of 1938378311 is about 1246.8460886473.

The spelling of 1938378311 in words is "one billion, nine hundred thirty-eight million, three hundred seventy-eight thousand, three hundred eleven".