1640063626 has 4 divisors (see below), whose sum is σ = 2460095442. Its totient is φ = 820031812.

The previous prime is 1640063617. The next prime is 1640063639. The reversal of 1640063626 is 6263600461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6263600461 = 43 ⋅145665127.

It can be written as a sum of positive squares in only one way, i.e., 1486179601 + 153884025 = 38551^2 + 12405^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1640063591 and 1640063600.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410015905 + ... + 410015908.

Almost surely, 2^1640063626 is an apocalyptic number.

1640063626 is a deficient number, since it is larger than the sum of its proper divisors (820031816).

1640063626 is an equidigital number, since it uses as much as digits as its factorization.

1640063626 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 820031815.

The product of its (nonzero) digits is 31104, while the sum is 34.

The square root of 1640063626 is about 40497.6990210555. The cubic root of 1640063626 is about 1179.2889582987.

The spelling of 1640063626 in words is "one billion, six hundred forty million, sixty-three thousand, six hundred twenty-six".