5428721691 has 24 divisors (see below), whose sum is σ = 7931465360. Its totient is φ = 3577706496.

The previous prime is 5428721689. The next prime is 5428721693. The reversal of 5428721691 is 1961278245.

5428721691 is a `hidden beast` number, since 5 + 428 + 7 + 216 + 9 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (5428721689) and next prime (5428721693).

It is not a de Polignac number, because 5428721691 - 2¹ = 5428721689 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (5428721693) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 877776 + ... + 883938.

Almost surely, 2^5428721691 is an apocalyptic number.

5428721691 is a deficient number, since it is larger than the sum of its proper divisors (2502743669).

5428721691 is a wasteful number, since it uses less digits than its factorization.

5428721691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7275 (or 7272 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The square root of 5428721691 is about 73679.8594664784. The cubic root of 5428721691 is about 1757.5156161019.

The spelling of 5428721691 in words is "five billion, four hundred twenty-eight million, seven hundred twenty-one thousand, six hundred ninety-one".