61997769 has 6 divisors (see below), whose sum is σ = 89552346. Its totient is φ = 41331840.

The previous prime is 61997711. The next prime is 61997797. The reversal of 61997769 is 96779916.

It can be written as a sum of positive squares in only one way, i.e., 52925625 + 9072144 = 7275^2 + 3012^2 .

It is not a de Polignac number, because 61997769 - 2⁷ = 61997641 is a prime.

It is a super-2 number, since 2×61997769² = 7687446721954722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (61997069) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3444312 + ... + 3444329.

It is an arithmetic number, because the mean of its divisors is an integer number (14925391).

Almost surely, 2^61997769 is an apocalyptic number.

It is an amenable number.

61997769 is a deficient number, since it is larger than the sum of its proper divisors (27554577).

61997769 is a wasteful number, since it uses less digits than its factorization.

61997769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6888647 (or 6888644 counting only the distinct ones).

The product of its digits is 1285956, while the sum is 54.

The square root of 61997769 is about 7873.8662040957. The cubic root of 61997769 is about 395.7844135691.

The spelling of 61997769 in words is "sixty-one million, nine hundred ninety-seven thousand, seven hundred sixty-nine".