21298156774 has 4 divisors (see below), whose sum is σ = 31947235164. Its totient is φ = 10649078386.

The previous prime is 21298156751. The next prime is 21298156777. The reversal of 21298156774 is 47765189212.

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

It is a super-2 number, since 2×21298156774² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21298156777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5324539192 + ... + 5324539195.

It is an arithmetic number, because the mean of its divisors is an integer number (7986808791).

Almost surely, 2^21298156774 is an apocalyptic number.

21298156774 is a deficient number, since it is larger than the sum of its proper divisors (10649078390).

21298156774 is a wasteful number, since it uses less digits than its factorization.

21298156774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10649078389.

The product of its digits is 1693440, while the sum is 52.

The spelling of 21298156774 in words is "twenty-one billion, two hundred ninety-eight million, one hundred fifty-six thousand, seven hundred seventy-four".