2156778104 has 32 divisors (see below), whose sum is σ = 4461261840. Its totient is φ = 971155200.

The previous prime is 2156778101. The next prime is 2156778163. The reversal of 2156778104 is 4018776512.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2156778101) 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 7 ways as a sum of consecutive naturals, for example, 248642 + ... + 257169.

Almost surely, 2^2156778104 is an apocalyptic number.

It is an amenable number.

2156778104 is an abundant number, since it is smaller than the sum of its proper divisors (2304483736).

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

2156778104 is a wasteful number, since it uses less digits than its factorization.

2156778104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 505871 (or 505867 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 41.

The square root of 2156778104 is about 46441.1251371024. The cubic root of 2156778104 is about 1292.0177752541.

The spelling of 2156778104 in words is "two billion, one hundred fifty-six million, seven hundred seventy-eight thousand, one hundred four".