849197661 has 16 divisors (see below), whose sum is σ = 1226418816. Its totient is φ = 519558336.

The previous prime is 849197639. The next prime is 849197759. The reversal of 849197661 is 166791948.

It is a happy number.

It is not a de Polignac number, because 849197661 - 2¹³ = 849189469 is a prime.

It is a super-2 number, since 2×849197661² = 1442273334895741842, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (849197621) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56185 + ... + 69678.

It is an arithmetic number, because the mean of its divisors is an integer number (76651176).

Almost surely, 2^849197661 is an apocalyptic number.

It is an amenable number.

849197661 is a deficient number, since it is larger than the sum of its proper divisors (377221155).

849197661 is a wasteful number, since it uses less digits than its factorization.

849197661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126052.

The product of its digits is 653184, while the sum is 51.

The square root of 849197661 is about 29140.9962252494. The cubic root of 849197661 is about 946.9700922786.

The spelling of 849197661 in words is "eight hundred forty-nine million, one hundred ninety-seven thousand, six hundred sixty-one".