1656864870 has 16 divisors (see below), whose sum is σ = 3976475760. Its totient is φ = 441830624.

The previous prime is 1656864799. The next prime is 1656864883. The reversal of 1656864870 is 784686561.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27614385 + ... + 27614444.

It is an arithmetic number, because the mean of its divisors is an integer number (248529735).

Almost surely, 2^1656864870 is an apocalyptic number.

1656864870 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1656864870 is an abundant number, since it is smaller than the sum of its proper divisors (2319610890).

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

1656864870 is a wasteful number, since it uses less digits than its factorization.

1656864870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55228839.

The product of its (nonzero) digits is 1935360, while the sum is 51.

The square root of 1656864870 is about 40704.6050220365. The cubic root of 1656864870 is about 1183.3022671648.

The spelling of 1656864870 in words is "one billion, six hundred fifty-six million, eight hundred sixty-four thousand, eight hundred seventy".