70724557 has 2 divisors, whose sum is σ = 70724558. Its totient is φ = 70724556.

The previous prime is 70724531. The next prime is 70724569. The reversal of 70724557 is 75542707.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52113961 + 18610596 = 7219^2 + 4314^2 .

It is an emirp because it is prime and its reverse (75542707) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 70724557 - 2⁷ = 70724429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (70724957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35362278 + 35362279.

It is an arithmetic number, because the mean of its divisors is an integer number (35362279).

Almost surely, 2^70724557 is an apocalyptic number.

It is an amenable number.

70724557 is a deficient number, since it is larger than the sum of its proper divisors (1).

70724557 is an equidigital number, since it uses as much as digits as its factorization.

70724557 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 68600, while the sum is 37.

The square root of 70724557 is about 8409.7893552693. The cubic root of 70724557 is about 413.5456071603.

The spelling of 70724557 in words is "seventy million, seven hundred twenty-four thousand, five hundred fifty-seven".