1656105978 has 8 divisors (see below), whose sum is σ = 3312211968. Its totient is φ = 552035324.

The previous prime is 1656105973. The next prime is 1656106013. The reversal of 1656105978 is 8795016561.

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

1656105978 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (1656105973) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 138008826 + ... + 138008837.

It is an arithmetic number, because the mean of its divisors is an integer number (414026496).

Almost surely, 2^1656105978 is an apocalyptic number.

1656105978 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.

1656105978 is a wasteful number, since it uses less digits than its factorization.

1656105978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276017668.

The product of its (nonzero) digits is 453600, while the sum is 48.

The square root of 1656105978 is about 40695.2820115551. The cubic root of 1656105978 is about 1183.1215773615.

The spelling of 1656105978 in words is "one billion, six hundred fifty-six million, one hundred five thousand, nine hundred seventy-eight".