2157445749 has 16 divisors (see below), whose sum is σ = 3005262720. Its totient is φ = 1374945600.

The previous prime is 2157445739. The next prime is 2157445811. The reversal of 2157445749 is 9475447512.

It is not a de Polignac number, because 2157445749 - 2⁴ = 2157445733 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2157445698 and 2157445707.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2157445729) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 113977 + ... + 131550.

It is an arithmetic number, because the mean of its divisors is an integer number (187828920).

Almost surely, 2^2157445749 is an apocalyptic number.

2157445749 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

2157445749 is a deficient number, since it is larger than the sum of its proper divisors (847816971).

2157445749 is a wasteful number, since it uses less digits than its factorization.

2157445749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245660.

The product of its digits is 1411200, while the sum is 48.

The square root of 2157445749 is about 46448.3126604186. The cubic root of 2157445749 is about 1292.1510790638.

The spelling of 2157445749 in words is "two billion, one hundred fifty-seven million, four hundred forty-five thousand, seven hundred forty-nine".