1642528997 has 4 divisors (see below), whose sum is σ = 1642611180. Its totient is φ = 1642446816.

The previous prime is 1642528931. The next prime is 1642529029. The reversal of 1642528997 is 7998252461.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 919241761 + 723287236 = 30319^2 + 26894^2 .

It is a cyclic number.

It is not a de Polignac number, because 1642528997 - 2¹⁸ = 1642266853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1642528297) 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, 10379 + ... + 58247.

It is an arithmetic number, because the mean of its divisors is an integer number (410652795).

Almost surely, 2^1642528997 is an apocalyptic number.

It is an amenable number.

1642528997 is a deficient number, since it is larger than the sum of its proper divisors (82183).

1642528997 is an equidigital number, since it uses as much as digits as its factorization.

1642528997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82182.

The product of its digits is 2177280, while the sum is 53.

The square root of 1642528997 is about 40528.1259991133. The cubic root of 1642528997 is about 1179.8795714021.

The spelling of 1642528997 in words is "one billion, six hundred forty-two million, five hundred twenty-eight thousand, nine hundred ninety-seven".