15867778640 has 160 divisors (see below), whose sum is σ = 42892540416. Its totient is φ = 5346754560.

The previous prime is 15867778621. The next prime is 15867778643. The reversal of 15867778640 is 4687776851.

It is a self number, because there is not a number n which added to its sum of digits gives 15867778640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15867778643) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23577344 + ... + 23578016.

Almost surely, 2^15867778640 is an apocalyptic number.

15867778640 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 15867778640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21446270208).

15867778640 is an abundant number, since it is smaller than the sum of its proper divisors (27024761776).

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

15867778640 is a wasteful number, since it uses less digits than its factorization.

15867778640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1357 (or 1351 counting only the distinct ones).

The product of its (nonzero) digits is 15805440, while the sum is 59.

The spelling of 15867778640 in words is "fifteen billion, eight hundred sixty-seven million, seven hundred seventy-eight thousand, six hundred forty".