71963781 has 4 divisors (see below), whose sum is σ = 95951712. Its totient is φ = 47975852.

The previous prime is 71963747. The next prime is 71963783. The reversal of 71963781 is 18736917.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 71963781 - 2¹⁹ = 71439493 is a prime.

It is a super-2 number, since 2×71963781² = 10357571551631922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71963783) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11993961 + ... + 11993966.

It is an arithmetic number, because the mean of its divisors is an integer number (23987928).

Almost surely, 2^71963781 is an apocalyptic number.

It is an amenable number.

71963781 is a deficient number, since it is larger than the sum of its proper divisors (23987931).

71963781 is a wasteful number, since it uses less digits than its factorization.

71963781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23987930.

The product of its digits is 63504, while the sum is 42.

The square root of 71963781 is about 8483.1468807277. The cubic root of 71963781 is about 415.9469949879.

The spelling of 71963781 in words is "seventy-one million, nine hundred sixty-three thousand, seven hundred eighty-one".