15405380640 has 288 divisors, whose sum is σ = 57151313856. Its totient is φ = 3756165120.

The previous prime is 15405380623. The next prime is 15405380659. The reversal of 15405380640 is 4608350451.

It is a happy number.

15405380640 is a `hidden beast` number, since 1 + 5 + 4 + 0 + 5 + 3 + 8 + 0 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 15405380595 and 15405380604.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1999195 + ... + 2006885.

It is an arithmetic number, because the mean of its divisors is an integer number (198442062).

Almost surely, 2^15405380640 is an apocalyptic number.

15405380640 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 15405380640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28575656928).

15405380640 is an abundant number, since it is smaller than the sum of its proper divisors (41745933216).

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

15405380640 is a wasteful number, since it uses less digits than its factorization.

15405380640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7832 (or 7821 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

The spelling of 15405380640 in words is "fifteen billion, four hundred five million, three hundred eighty thousand, six hundred forty".