11661938415 has 16 divisors (see below), whose sum is σ = 20732335200. Its totient is φ = 6219700416.

The previous prime is 11661938381. The next prime is 11661938417. The reversal of 11661938415 is 51483916611.

11661938415 is a `hidden beast` number, since 1 + 16 + 619 + 3 + 8 + 4 + 15 = 666.

It is not a de Polignac number, because 11661938415 - 2¹³ = 11661930223 is a prime.

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 (11661938417) 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, 43192230 + ... + 43192499.

It is an arithmetic number, because the mean of its divisors is an integer number (1295770950).

Almost surely, 2^11661938415 is an apocalyptic number.

11661938415 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

11661938415 is a deficient number, since it is larger than the sum of its proper divisors (9070396785).

11661938415 is an equidigital number, since it uses as much as digits as its factorization.

11661938415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86384743 (or 86384737 counting only the distinct ones).

The product of its digits is 155520, while the sum is 45.

The spelling of 11661938415 in words is "eleven billion, six hundred sixty-one million, nine hundred thirty-eight thousand, four hundred fifteen".