21135747674 has 4 divisors (see below), whose sum is σ = 31703621514. Its totient is φ = 10567873836.

The previous prime is 21135747667. The next prime is 21135747697. The reversal of 21135747674 is 47674753112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 21116449225 + 19298449 = 145315^2 + 4393^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5283936917 + ... + 5283936920.

Almost surely, 2^21135747674 is an apocalyptic number.

21135747674 is a deficient number, since it is larger than the sum of its proper divisors (10567873840).

21135747674 is a wasteful number, since it uses less digits than its factorization.

21135747674 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10567873839.

The product of its digits is 987840, while the sum is 47.

The spelling of 21135747674 in words is "twenty-one billion, one hundred thirty-five million, seven hundred forty-seven thousand, six hundred seventy-four".