15778472748491 has 4 divisors (see below), whose sum is σ = 15778497983184. Its totient is φ = 15778447513800.

The previous prime is 15778472748443. The next prime is 15778472748499. The reversal of 15778472748491 is 19484727487751.

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 15778472748491 - 2³⁸ = 15503594841547 is a prime.

It is a super-3 number, since 3×15778472748491³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15778472748499) 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, 11654975 + ... + 12938136.

It is an arithmetic number, because the mean of its divisors is an integer number (3944624495796).

Almost surely, 2^{15778472748491} is an apocalyptic number.

15778472748491 is a deficient number, since it is larger than the sum of its proper divisors (25234693).

15778472748491 is an equidigital number, since it uses as much as digits as its factorization.

15778472748491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25234692.

The product of its digits is 885104640, while the sum is 74.

The spelling of 15778472748491 in words is "fifteen trillion, seven hundred seventy-eight billion, four hundred seventy-two million, seven hundred forty-eight thousand, four hundred ninety-one".