15551662447 has 4 divisors (see below), whose sum is σ = 15637583416. Its totient is φ = 15465741480.

The previous prime is 15551662433. The next prime is 15551662471. The reversal of 15551662447 is 74426615551.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 15551662447 - 2⁷ = 15551662319 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 15551662397 and 15551662406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15551662487) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42960213 + ... + 42960574.

It is an arithmetic number, because the mean of its divisors is an integer number (3909395854).

Almost surely, 2^15551662447 is an apocalyptic number.

15551662447 is a deficient number, since it is larger than the sum of its proper divisors (85920969).

15551662447 is an equidigital number, since it uses as much as digits as its factorization.

15551662447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85920968.

The product of its digits is 1008000, while the sum is 46.

The spelling of 15551662447 in words is "fifteen billion, five hundred fifty-one million, six hundred sixty-two thousand, four hundred forty-seven".