70720861 has 2 divisors, whose sum is σ = 70720862. Its totient is φ = 70720860.

The previous prime is 70720847. The next prime is 70720877. The reversal of 70720861 is 16802707.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 70660836 + 60025 = 8406^2 + 245^2 .

It is a cyclic number.

It is not a de Polignac number, because 70720861 - 2⁵ = 70720829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (70720891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35360430 + 35360431.

It is an arithmetic number, because the mean of its divisors is an integer number (35360431).

Almost surely, 2^70720861 is an apocalyptic number.

It is an amenable number.

70720861 is a deficient number, since it is larger than the sum of its proper divisors (1).

70720861 is an equidigital number, since it uses as much as digits as its factorization.

70720861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4704, while the sum is 31.

The square root of 70720861 is about 8409.5696084877. The cubic root of 70720861 is about 413.5384031977.

The spelling of 70720861 in words is "seventy million, seven hundred twenty thousand, eight hundred sixty-one".