70236781 has 2 divisors, whose sum is σ = 70236782. Its totient is φ = 70236780.

The previous prime is 70236773. The next prime is 70236797. The reversal of 70236781 is 18763207.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66683556 + 3553225 = 8166^2 + 1885^2 .

It is an emirp because it is prime and its reverse (18763207) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 70236781 - 2³ = 70236773 is a prime.

It is a super-2 number, since 2×70236781² = 9866410810483922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (70236701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35118390 + 35118391.

It is an arithmetic number, because the mean of its divisors is an integer number (35118391).

Almost surely, 2^70236781 is an apocalyptic number.

It is an amenable number.

70236781 is a deficient number, since it is larger than the sum of its proper divisors (1).

70236781 is an equidigital number, since it uses as much as digits as its factorization.

70236781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14112, while the sum is 34.

The square root of 70236781 is about 8380.7386905929. The cubic root of 70236781 is about 412.5926937084.

Adding to 70236781 its reverse (18763207), we get a palindrome (88999988).

It can be divided in two parts, 70236 and 781, that added together give a palindrome (71017).

The spelling of 70236781 in words is "seventy million, two hundred thirty-six thousand, seven hundred eighty-one".