1649561760 has 1152 divisors, whose sum is σ = 7925299200. Its totient is φ = 313528320.

The previous prime is 1649561729. The next prime is 1649561761. The reversal of 1649561760 is 671659461.

1649561760 is a `hidden beast` number, since 16 + 4 + 9 + 561 + 76 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1649561761) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 56881426 + ... + 56881454.

It is an arithmetic number, because the mean of its divisors is an integer number (6879600).

Almost surely, 2^1649561760 is an apocalyptic number.

1649561760 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1649561760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3962649600).

1649561760 is an abundant number, since it is smaller than the sum of its proper divisors (6275737440).

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

1649561760 is a wasteful number, since it uses less digits than its factorization.

1649561760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96 (or 76 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The square root of 1649561760 is about 40614.7973034459. The cubic root of 1649561760 is about 1181.5611243963.

The spelling of 1649561760 in words is "one billion, six hundred forty-nine million, five hundred sixty-one thousand, seven hundred sixty".