21909492722 has 8 divisors (see below), whose sum is σ = 35392257516. Its totient is φ = 10112073552.

The previous prime is 21909492719. The next prime is 21909492763. The reversal of 21909492722 is 22729490912.

It can be written as a sum of positive squares in 2 ways, for example, as 17763291841 + 4146200881 = 133279^2 + 64391^2 .

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

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, 421336373 + ... + 421336424.

Almost surely, 2^21909492722 is an apocalyptic number.

21909492722 is a deficient number, since it is larger than the sum of its proper divisors (13482764794).

21909492722 is a wasteful number, since it uses less digits than its factorization.

21909492722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 842672812.

The product of its (nonzero) digits is 326592, while the sum is 47.

The spelling of 21909492722 in words is "twenty-one billion, nine hundred nine million, four hundred ninety-two thousand, seven hundred twenty-two".