1097749861 has 8 divisors (see below), whose sum is σ = 1185175544. Its totient is φ = 1010750400.

The previous prime is 1097749843. The next prime is 1097749879. The reversal of 1097749861 is 1689477901.

It is an interprime number because it is at equal distance from previous prime (1097749843) and next prime (1097749879).

It can be written as a sum of positive squares in 4 ways, for example, as 212984836 + 884765025 = 14594^2 + 29745^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1097749861 - 2⁷ = 1097749733 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1097749799 and 1097749808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1097749361) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 101190 + ... + 111511.

It is an arithmetic number, because the mean of its divisors is an integer number (148146943).

Almost surely, 2^1097749861 is an apocalyptic number.

It is an amenable number.

1097749861 is a deficient number, since it is larger than the sum of its proper divisors (87425683).

1097749861 is a wasteful number, since it uses less digits than its factorization.

1097749861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213111.

The product of its (nonzero) digits is 762048, while the sum is 52.

The square root of 1097749861 is about 33132.3084164083. The cubic root of 1097749861 is about 1031.5757641363.

The spelling of 1097749861 in words is "one billion, ninety-seven million, seven hundred forty-nine thousand, eight hundred sixty-one".