1643642154 has 48 divisors (see below), whose sum is σ = 4439972160. Its totient is φ = 426919680.

The previous prime is 1643642113. The next prime is 1643642159. The reversal of 1643642154 is 4512463461.

1643642154 is a `hidden beast` number, since 1 + 6 + 4 + 3 + 642 + 1 + 5 + 4 = 666.

It is not an unprimeable number, because it can be changed into a prime (1643642159) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 591559 + ... + 594330.

It is an arithmetic number, because the mean of its divisors is an integer number (92499420).

Almost surely, 2^1643642154 is an apocalyptic number.

1643642154 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

1643642154 is an abundant number, since it is smaller than the sum of its proper divisors (2796330006).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1643642154 is a wasteful number, since it uses less digits than its factorization.

1643642154 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1185915 (or 1185912 counting only the distinct ones).

The product of its digits is 69120, while the sum is 36.

The square root of 1643642154 is about 40541.8568149018. The cubic root of 1643642154 is about 1180.1460496234.

The spelling of 1643642154 in words is "one billion, six hundred forty-three million, six hundred forty-two thousand, one hundred fifty-four".