1621702913 has 6 divisors (see below), whose sum is σ = 1717273026. Its totient is φ = 1526152352.

The previous prime is 1621702897. The next prime is 1621702919. The reversal of 1621702913 is 3192071261.

It can be written as a sum of positive squares in only one way, i.e., 1526308624 + 95394289 = 39068^2 + 9767^2 .

It is not a de Polignac number, because 1621702913 - 2⁴ = 1621702897 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1621702913.

It is not an unprimeable number, because it can be changed into a prime (1621702919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 161156 + ... + 170922.

It is an arithmetic number, because the mean of its divisors is an integer number (286212171).

Almost surely, 2^1621702913 is an apocalyptic number.

It is an amenable number.

1621702913 is a deficient number, since it is larger than the sum of its proper divisors (95570113).

1621702913 is an frugal number, since it uses more digits than its factorization.

1621702913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19551 (or 9784 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 32.

The square root of 1621702913 is about 40270.3726454077. The cubic root of 1621702913 is about 1174.8716716347.

The spelling of 1621702913 in words is "one billion, six hundred twenty-one million, seven hundred two thousand, nine hundred thirteen".