2157678942 has 8 divisors (see below), whose sum is σ = 4315357896. Its totient is φ = 719226312.

The previous prime is 2157678923. The next prime is 2157678977. The reversal of 2157678942 is 2498767512.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

2157678942 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 179806573 + ... + 179806584.

It is an arithmetic number, because the mean of its divisors is an integer number (539419737).

Almost surely, 2^2157678942 is an apocalyptic number.

2157678942 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

2157678942 is a wasteful number, since it uses less digits than its factorization.

2157678942 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 359613162.

The product of its digits is 1693440, while the sum is 51.

The square root of 2157678942 is about 46450.8228344773. The cubic root of 2157678942 is about 1292.1976325297.

The spelling of 2157678942 in words is "two billion, one hundred fifty-seven million, six hundred seventy-eight thousand, nine hundred forty-two".