16164551978 has 24 divisors (see below), whose sum is σ = 24785020260. Its totient is φ = 7906757976.

The previous prime is 16164551957. The next prime is 16164551981. The reversal of 16164551978 is 87915546161.

It can be written as a sum of positive squares in 2 ways, for example, as 16036929769 + 127622209 = 126637^2 + 11297^2 .

It is a super-2 number, since 2×16164551978² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 148298588 + ... + 148298696.

Almost surely, 2^16164551978 is an apocalyptic number.

16164551978 is a deficient number, since it is larger than the sum of its proper divisors (8620468282).

16164551978 is an frugal number, since it uses more digits than its factorization.

16164551978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 487 (or 190 counting only the distinct ones).

The product of its digits is 1814400, while the sum is 53.

The spelling of 16164551978 in words is "sixteen billion, one hundred sixty-four million, five hundred fifty-one thousand, nine hundred seventy-eight".