21430491562 has 4 divisors (see below), whose sum is σ = 32145737346. Its totient is φ = 10715245780.

The previous prime is 21430491547. The next prime is 21430491581. The reversal of 21430491562 is 26519403412.

It is a happy number.

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., 21368884761 + 61606801 = 146181^2 + 7849^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5357622889 + ... + 5357622892.

Almost surely, 2^21430491562 is an apocalyptic number.

21430491562 is a deficient number, since it is larger than the sum of its proper divisors (10715245784).

21430491562 is a wasteful number, since it uses less digits than its factorization.

21430491562 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10715245783.

The product of its (nonzero) digits is 51840, while the sum is 37.

Adding to 21430491562 its reverse (26519403412), we get a palindrome (47949894974).

The spelling of 21430491562 in words is "twenty-one billion, four hundred thirty million, four hundred ninety-one thousand, five hundred sixty-two".