15391220040 has 384 divisors, whose sum is σ = 61273704960. Its totient is φ = 3273633792.

The previous prime is 15391220029. The next prime is 15391220057. The reversal of 15391220040 is 4002219351.

15391220040 is a `hidden beast` number, since 1 + 539 + 122 + 0 + 0 + 4 + 0 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 15391219986 and 15391220013.

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, 2140932 + ... + 2148108.

It is an arithmetic number, because the mean of its divisors is an integer number (159566940).

Almost surely, 2^15391220040 is an apocalyptic number.

15391220040 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 15391220040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30636852480).

15391220040 is an abundant number, since it is smaller than the sum of its proper divisors (45882484920).

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

15391220040 is a wasteful number, since it uses less digits than its factorization.

15391220040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7261 (or 7254 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

Adding to 15391220040 its reverse (4002219351), we get a palindrome (19393439391).

The spelling of 15391220040 in words is "fifteen billion, three hundred ninety-one million, two hundred twenty thousand, forty".