21155062546 has 4 divisors (see below), whose sum is σ = 31732593822. Its totient is φ = 10577531272.

The previous prime is 21155062457. The next prime is 21155062549. The reversal of 21155062546 is 64526055112.

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., 13539882321 + 7615180225 = 116361^2 + 87265^2 .

It is not an unprimeable number, because it can be changed into a prime (21155062549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5288765635 + ... + 5288765638.

Almost surely, 2^21155062546 is an apocalyptic number.

21155062546 is a deficient number, since it is larger than the sum of its proper divisors (10577531276).

21155062546 is a wasteful number, since it uses less digits than its factorization.

21155062546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10577531275.

The product of its (nonzero) digits is 72000, while the sum is 37.

The spelling of 21155062546 in words is "twenty-one billion, one hundred fifty-five million, sixty-two thousand, five hundred forty-six".