1643157650 has 24 divisors (see below), whose sum is σ = 3063932244. Its totient is φ = 655616000.

The previous prime is 1643157643. The next prime is 1643157653. The reversal of 1643157650 is 567513461.

It can be written as a sum of positive squares in 6 ways, for example, as 937033321 + 706124329 = 30611^2 + 26573^2 .

It is a hoax number, since the sum of its digits (38) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (1643157653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20927 + ... + 61026.

Almost surely, 2^1643157650 is an apocalyptic number.

1643157650 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1643157650 is a deficient number, since it is larger than the sum of its proper divisors (1420774594).

1643157650 is a wasteful number, since it uses less digits than its factorization.

1643157650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82366 (or 82361 counting only the distinct ones).

The product of its (nonzero) digits is 75600, while the sum is 38.

The square root of 1643157650 is about 40535.8810191662. The cubic root of 1643157650 is about 1180.0300791911.

The spelling of 1643157650 in words is "one billion, six hundred forty-three million, one hundred fifty-seven thousand, six hundred fifty".