21072779519 has 8 divisors (see below), whose sum is σ = 23030519808. Its totient is φ = 19122044760.

The previous prime is 21072779509. The next prime is 21072779591. The reversal of 21072779519 is 91597727012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21072779519 - 2⁴ = 21072779503 is a prime.

It is a super-2 number, since 2×21072779519² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21072779509) by changing a digit.

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 in 7 ways as a sum of consecutive naturals, for example, 1745087 + ... + 1757120.

It is an arithmetic number, because the mean of its divisors is an integer number (2878814976).

Almost surely, 2^21072779519 is an apocalyptic number.

21072779519 is a deficient number, since it is larger than the sum of its proper divisors (1957740289).

21072779519 is a wasteful number, since it uses less digits than its factorization.

21072779519 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3502765.

The product of its (nonzero) digits is 555660, while the sum is 50.

The spelling of 21072779519 in words is "twenty-one billion, seventy-two million, seven hundred seventy-nine thousand, five hundred nineteen".