199626665616 has 405 divisors, whose sum is σ = 678294556329. Its totient is φ = 56746666368.

The previous prime is 199626665593. The next prime is 199626665617. The reversal of 199626665616 is 616566626991.

It is a happy number.

The square root of 199626665616 is 446796.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 195593907600 + 4032758016 = 442260^2 + 63504^2 .

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (199626665617) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 1013333230 + ... + 1013333426.

Almost surely, 2^199626665616 is an apocalyptic number.

199626665616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

199626665616 is the 446796-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 199626665616

199626665616 is an abundant number, since it is smaller than the sum of its proper divisors (478667890713).

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

199626665616 is an frugal number, since it uses more digits than its factorization.

199626665616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 440 (or 209 counting only the distinct ones).

The product of its digits is 37791360, while the sum is 63.

The spelling of 199626665616 in words is "one hundred ninety-nine billion, six hundred twenty-six million, six hundred sixty-five thousand, six hundred sixteen".