1642540426 has 4 divisors (see below), whose sum is σ = 2463810642. Its totient is φ = 821270212.

The previous prime is 1642540421. The next prime is 1642540457. The reversal of 1642540426 is 6240452461.

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

It can be written as a sum of positive squares in only one way, i.e., 1451686201 + 190854225 = 38101^2 + 13815^2 .

It is a super-2 number, since 2×1642540426² = 5395878102088522952, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1642540391 and 1642540400.

It is not an unprimeable number, because it can be changed into a prime (1642540421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410635105 + ... + 410635108.

Almost surely, 2^1642540426 is an apocalyptic number.

1642540426 is a deficient number, since it is larger than the sum of its proper divisors (821270216).

1642540426 is an equidigital number, since it uses as much as digits as its factorization.

1642540426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 821270215.

The product of its (nonzero) digits is 46080, while the sum is 34.

The square root of 1642540426 is about 40528.2669997127. The cubic root of 1642540426 is about 1179.8823079976.

Adding to 1642540426 its reverse (6240452461), we get a palindrome (7882992887).

The spelling of 1642540426 in words is "one billion, six hundred forty-two million, five hundred forty thousand, four hundred twenty-six".