53989721 has 2 divisors, whose sum is σ = 53989722. Its totient is φ = 53989720.

The previous prime is 53989709. The next prime is 53989723. The reversal of 53989721 is 12798935.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27415696 + 26574025 = 5236^2 + 5155^2 .

It is a cyclic number.

It is not a de Polignac number, because 53989721 - 2¹⁸ = 53727577 is a prime.

Together with 53989723, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (53989723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26994860 + 26994861.

It is an arithmetic number, because the mean of its divisors is an integer number (26994861).

Almost surely, 2^53989721 is an apocalyptic number.

It is an amenable number.

53989721 is a deficient number, since it is larger than the sum of its proper divisors (1).

53989721 is an equidigital number, since it uses as much as digits as its factorization.

53989721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 136080, while the sum is 44.

The square root of 53989721 is about 7347.7697977005. The cubic root of 53989721 is about 377.9523306161.

The spelling of 53989721 in words is "fifty-three million, nine hundred eighty-nine thousand, seven hundred twenty-one".