1553696640 has 640 divisors, whose sum is σ = 6158164320. Its totient is φ = 371589120.

The previous prime is 1553696593. The next prime is 1553696647. The reversal of 1553696640 is 466963551.

1553696640 is a `hidden beast` number, since 1 + 553 + 6 + 96 + 6 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (640).

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 (1553696647) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 36132459 + ... + 36132501.

Almost surely, 2^1553696640 is an apocalyptic number.

1553696640 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 1553696640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3079082160).

1553696640 is an abundant number, since it is smaller than the sum of its proper divisors (4604467680).

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

1553696640 is a wasteful number, since it uses less digits than its factorization.

1553696640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132 (or 111 counting only the distinct ones).

The product of its (nonzero) digits is 583200, while the sum is 45.

The square root of 1553696640 is about 39416.9587867963. The cubic root of 1553696640 is about 1158.2138186072.

The spelling of 1553696640 in words is "one billion, five hundred fifty-three million, six hundred ninety-six thousand, six hundred forty".