16115861606400 has 1560 divisors, whose sum is σ = 64937949519960. Its totient is φ = 3934173265920.

The previous prime is 16115861606353. The next prime is 16115861606401. The reversal of 16115861606400 is 460616851161.

16115861606400 is a `hidden beast` number, since 1 + 6 + 1 + 1 + 5 + 86 + 160 + 6 + 400 = 666.

It can be written as a sum of positive squares in 12 ways, for example, as 127123623936 + 15988737982464 = 356544^2 + 3998592^2 .

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 (16115861606401) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 5217176056 + ... + 5217179144.

Almost surely, 2^{16115861606400} is an apocalyptic number.

16115861606400 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 16115861606400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32468974759980).

16115861606400 is an abundant number, since it is smaller than the sum of its proper divisors (48822087913560).

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

16115861606400 is a wasteful number, since it uses less digits than its factorization.

16115861606400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3189 (or 3153 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The spelling of 16115861606400 in words is "sixteen trillion, one hundred fifteen billion, eight hundred sixty-one million, six hundred six thousand, four hundred".