70939681 has 2 divisors, whose sum is σ = 70939682. Its totient is φ = 70939680.

The previous prime is 70939663. The next prime is 70939697. The reversal of 70939681 is 18693907.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60699681 + 10240000 = 7791^2 + 3200^2 .

It is an emirp because it is prime and its reverse (18693907) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 70939681 - 2¹³ = 70931489 is a prime.

It is a super-2 number, since 2×70939681² = 10064876680763522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (70939651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35469840 + 35469841.

It is an arithmetic number, because the mean of its divisors is an integer number (35469841).

Almost surely, 2^70939681 is an apocalyptic number.

It is an amenable number.

70939681 is a deficient number, since it is larger than the sum of its proper divisors (1).

70939681 is an equidigital number, since it uses as much as digits as its factorization.

70939681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 81648, while the sum is 43.

The square root of 70939681 is about 8422.5697385062. The cubic root of 70939681 is about 413.9644788150.

The spelling of 70939681 in words is "seventy million, nine hundred thirty-nine thousand, six hundred eighty-one".