21771107252 has 6 divisors (see below), whose sum is σ = 38099437698. Its totient is φ = 10885553624.

The previous prime is 21771107249. The next prime is 21771107333. The reversal of 21771107252 is 25270117712.

It can be written as a sum of positive squares in only one way, i.e., 17927603236 + 3843504016 = 133894^2 + 61996^2 .

It is a super-2 number, since 2×21771107252² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2721388403 + ... + 2721388410.

It is an arithmetic number, because the mean of its divisors is an integer number (6349906283).

Almost surely, 2^21771107252 is an apocalyptic number.

It is an amenable number.

21771107252 is a deficient number, since it is larger than the sum of its proper divisors (16328330446).

21771107252 is a wasteful number, since it uses less digits than its factorization.

21771107252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5442776817 (or 5442776815 counting only the distinct ones).

The product of its (nonzero) digits is 13720, while the sum is 35.

The spelling of 21771107252 in words is "twenty-one billion, seven hundred seventy-one million, one hundred seven thousand, two hundred fifty-two".