2156340 has 48 divisors (see below), whose sum is σ = 6124608. Its totient is φ = 566784.

The previous prime is 2156339. The next prime is 2156351. The reversal of 2156340 is 436512.

It is a happy number.

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4764 + ... + 5196.

It is an arithmetic number, because the mean of its divisors is an integer number (127596).

2^2156340 is an apocalyptic number.

2156340 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 2156340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3062304).

2156340 is an abundant number, since it is smaller than the sum of its proper divisors (3968268).

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

2156340 is a wasteful number, since it uses less digits than its factorization.

2156340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 528 (or 526 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 2156340 is about 1468.4481604742. The cubic root of 2156340 is about 129.1930287273.

It can be divided in two parts, 215 and 6340, that added together give a triangular number (6555 = T₁₁₄).

The spelling of 2156340 in words is "two million, one hundred fifty-six thousand, three hundred forty".