1649435749920 has 576 divisors, whose sum is σ = 6798538656000. Its totient is φ = 377009966592.

The previous prime is 1649435749903. The next prime is 1649435749937. The reversal of 1649435749920 is 299475349461.

1649435749920 is a `hidden beast` number, since 1 + 6 + 4 + 94 + 3 + 57 + 499 + 2 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (1649435749903) and next prime (1649435749937).

It is a super-2 number, since 2×1649435749920² (a number of 25 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 17097981 + ... + 17194179.

It is an arithmetic number, because the mean of its divisors is an integer number (11803018500).

Almost surely, 2^{1649435749920} is an apocalyptic number.

1649435749920 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 1649435749920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3399269328000).

1649435749920 is an abundant number, since it is smaller than the sum of its proper divisors (5149102906080).

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

1649435749920 is an frugal number, since it uses more digits than its factorization.

1649435749920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96249 (or 96216 counting only the distinct ones).

The product of its (nonzero) digits is 58786560, while the sum is 63.

The spelling of 1649435749920 in words is "one trillion, six hundred forty-nine billion, four hundred thirty-five million, seven hundred forty-nine thousand, nine hundred twenty".