1540662640 has 80 divisors (see below), whose sum is σ = 3948184800. Its totient is φ = 554434560.

The previous prime is 1540662619. The next prime is 1540662649. The reversal of 1540662640 is 462660451.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 1540662596 and 1540662605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1540662649) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76336 + ... + 94384.

It is an arithmetic number, because the mean of its divisors is an integer number (49352310).

Almost surely, 2^1540662640 is an apocalyptic number.

1540662640 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 1540662640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1974092400).

1540662640 is an abundant number, since it is smaller than the sum of its proper divisors (2407522160).

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

1540662640 is a wasteful number, since it uses less digits than its factorization.

1540662640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18170 (or 18164 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 34.

The square root of 1540662640 is about 39251.2756480602. The cubic root of 1540662640 is about 1154.9659579055.

The spelling of 1540662640 in words is "one billion, five hundred forty million, six hundred sixty-two thousand, six hundred forty".