19771493902 has 8 divisors (see below), whose sum is σ = 29658061800. Its totient is φ = 9885473304.

The previous prime is 19771493897. The next prime is 19771493909. The reversal of 19771493902 is 20939417791.

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

It is a super-2 number, since 2×19771493902² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 19771493902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19771493909) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29752 + ... + 201067.

It is an arithmetic number, because the mean of its divisors is an integer number (3707257725).

Almost surely, 2^19771493902 is an apocalyptic number.

19771493902 is a deficient number, since it is larger than the sum of its proper divisors (9886567898).

19771493902 is a wasteful number, since it uses less digits than its factorization.

19771493902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273650.

The product of its (nonzero) digits is 857304, while the sum is 52.

The spelling of 19771493902 in words is "nineteen billion, seven hundred seventy-one million, four hundred ninety-three thousand, nine hundred two".