2161977748 has 48 divisors (see below), whose sum is σ = 4361817600. Its totient is φ = 918489600.

The previous prime is 2161977743. The next prime is 2161977781. The reversal of 2161977748 is 8477791612.

It is a junction number, because it is equal to n+sod(n) for n = 2161977695 and 2161977704.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161977743) 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, 1799548 + ... + 1800748.

It is an arithmetic number, because the mean of its divisors is an integer number (90871200).

Almost surely, 2^2161977748 is an apocalyptic number.

2161977748 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

2161977748 is an abundant number, since it is smaller than the sum of its proper divisors (2199839852).

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

2161977748 is a wasteful number, since it uses less digits than its factorization.

2161977748 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1720 (or 1718 counting only the distinct ones).

The product of its digits is 1185408, while the sum is 52.

The square root of 2161977748 is about 46497.0724669844. The cubic root of 2161977748 is about 1293.0552241201.

The spelling of 2161977748 in words is "two billion, one hundred sixty-one million, nine hundred seventy-seven thousand, seven hundred forty-eight".