1620161543 has 32 divisors (see below), whose sum is σ = 2178785280. Its totient is φ = 1163496960.

The previous prime is 1620161519. The next prime is 1620161563. The reversal of 1620161543 is 3451610261.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1620161543 - 2⁸ = 1620161287 is a prime.

It is a super-2 number, since 2×1620161543² = 5249846850832281698, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620161563) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1087343 + ... + 1088831.

It is an arithmetic number, because the mean of its divisors is an integer number (68087040).

Almost surely, 2^1620161543 is an apocalyptic number.

1620161543 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

1620161543 is a deficient number, since it is larger than the sum of its proper divisors (558623737).

1620161543 is a wasteful number, since it uses less digits than its factorization.

1620161543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2607.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 1620161543 is about 40251.2303290222. The cubic root of 1620161543 is about 1174.4993292916.

The spelling of 1620161543 in words is "one billion, six hundred twenty million, one hundred sixty-one thousand, five hundred forty-three".