21048779642 has 8 divisors (see below), whose sum is σ = 34443457632. Its totient is φ = 9567627100.

The previous prime is 21048779639. The next prime is 21048779651. The reversal of 21048779642 is 24697784012.

It is a happy number.

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

It is a super-2 number, since 2×21048779642² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 478381334 + ... + 478381377.

It is an arithmetic number, because the mean of its divisors is an integer number (4305432204).

Almost surely, 2^21048779642 is an apocalyptic number.

21048779642 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21048779642 is a deficient number, since it is larger than the sum of its proper divisors (13394677990).

21048779642 is a wasteful number, since it uses less digits than its factorization.

21048779642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 956762724.

The product of its (nonzero) digits is 1354752, while the sum is 50.

The spelling of 21048779642 in words is "twenty-one billion, forty-eight million, seven hundred seventy-nine thousand, six hundred forty-two".