2138775780 has 96 divisors (see below), whose sum is σ = 6460642944. Its totient is φ = 526649344.

The previous prime is 2138775767. The next prime is 2138775799. The reversal of 2138775780 is 875778312.

It is a super-2 number, since 2×2138775780² = 9148723674229216800, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 34279 + ... + 73841.

It is an arithmetic number, because the mean of its divisors is an integer number (67298364).

Almost surely, 2^2138775780 is an apocalyptic number.

2138775780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2138775780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3230321472).

2138775780 is an abundant number, since it is smaller than the sum of its proper divisors (4321867164).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2138775780 is a wasteful number, since it uses less digits than its factorization.

2138775780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39645 (or 39643 counting only the distinct ones).

The product of its (nonzero) digits is 658560, while the sum is 48.

The square root of 2138775780 is about 46246.9002204472. The cubic root of 2138775780 is about 1288.4129633004.

The spelling of 2138775780 in words is "two billion, one hundred thirty-eight million, seven hundred seventy-five thousand, seven hundred eighty".