1645086638 has 16 divisors (see below), whose sum is σ = 2772989856. Its totient is φ = 726258720.

The previous prime is 1645086623. The next prime is 1645086659. The reversal of 1645086638 is 8366805461.

It is a super-2 number, since 2×1645086638² = 5412620093052286088, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1645086592 and 1645086601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1374893 + ... + 1376088.

It is an arithmetic number, because the mean of its divisors is an integer number (173311866).

Almost surely, 2^1645086638 is an apocalyptic number.

1645086638 is a deficient number, since it is larger than the sum of its proper divisors (1127903218).

1645086638 is a wasteful number, since it uses less digits than its factorization.

1645086638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2751019.

The product of its (nonzero) digits is 829440, while the sum is 47.

The square root of 1645086638 is about 40559.6676268433. The cubic root of 1645086638 is about 1180.4916647855.

The spelling of 1645086638 in words is "one billion, six hundred forty-five million, eighty-six thousand, six hundred thirty-eight".