73215553 has 2 divisors, whose sum is σ = 73215554. Its totient is φ = 73215552.

The previous prime is 73215547. The next prime is 73215557. The reversal of 73215553 is 35551237.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 56430144 + 16785409 = 7512^2 + 4097^2 .

It is a cyclic number.

It is not a de Polignac number, because 73215553 - 2⁹ = 73215041 is a prime.

It is not a weakly prime, because it can be changed into another prime (73215557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36607776 + 36607777.

It is an arithmetic number, because the mean of its divisors is an integer number (36607777).

Almost surely, 2^73215553 is an apocalyptic number.

It is an amenable number.

73215553 is a deficient number, since it is larger than the sum of its proper divisors (1).

73215553 is an equidigital number, since it uses as much as digits as its factorization.

73215553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15750, while the sum is 31.

The square root of 73215553 is about 8556.6087324360. The cubic root of 73215553 is about 418.3448711741.

The spelling of 73215553 in words is "seventy-three million, two hundred fifteen thousand, five hundred fifty-three".