71749621 has 2 divisors, whose sum is σ = 71749622. Its totient is φ = 71749620.

The previous prime is 71749619. The next prime is 71749637. The reversal of 71749621 is 12694717.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71216721 + 532900 = 8439^2 + 730^2 .

It is a cyclic number.

It is not a de Polignac number, because 71749621 - 2¹ = 71749619 is a prime.

It is a super-2 number, since 2×71749621² = 10296016227287282, which contains 22 as substring.

Together with 71749619, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71749661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35874810 + 35874811.

It is an arithmetic number, because the mean of its divisors is an integer number (35874811).

Almost surely, 2^71749621 is an apocalyptic number.

It is an amenable number.

71749621 is a deficient number, since it is larger than the sum of its proper divisors (1).

71749621 is an equidigital number, since it uses as much as digits as its factorization.

71749621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21168, while the sum is 37.

The square root of 71749621 is about 8470.5148013565. The cubic root of 71749621 is about 415.5339737040.

The spelling of 71749621 in words is "seventy-one million, seven hundred forty-nine thousand, six hundred twenty-one".