53821997 has 2 divisors, whose sum is σ = 53821998. Its totient is φ = 53821996.

The previous prime is 53821993. The next prime is 53822029. The reversal of 53821997 is 79912835.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43414921 + 10407076 = 6589^2 + 3226^2 .

It is a cyclic number.

It is not a de Polignac number, because 53821997 - 2² = 53821993 is a prime.

It is a super-2 number, since 2×53821997² = 5793614722136018, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (53821993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26910998 + 26910999.

It is an arithmetic number, because the mean of its divisors is an integer number (26910999).

Almost surely, 2^53821997 is an apocalyptic number.

It is an amenable number.

53821997 is a deficient number, since it is larger than the sum of its proper divisors (1).

53821997 is an equidigital number, since it uses as much as digits as its factorization.

53821997 is an evil number, because the sum of its binary digits is even.

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

The square root of 53821997 is about 7336.3476607914. The cubic root of 53821997 is about 377.5605434816.

The spelling of 53821997 in words is "fifty-three million, eight hundred twenty-one thousand, nine hundred ninety-seven".