19542921616 has 15 divisors (see below), whose sum is σ = 37865494081. Its totient is φ = 9771181216.

The previous prime is 19542921577. The next prime is 19542921641. The reversal of 19542921616 is 61612924591.

The square root of 19542921616 is 139796.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 806787216 + 18736134400 = 28404^2 + 136880^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 541710 + ... + 576658.

Almost surely, 2^19542921616 is an apocalyptic number.

19542921616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

19542921616 is the 139796-th square number.

It is an amenable number.

19542921616 is a deficient number, since it is larger than the sum of its proper divisors (18322572465).

19542921616 is an frugal number, since it uses more digits than its factorization.

19542921616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69906 (or 34951 counting only the distinct ones).

The product of its digits is 233280, while the sum is 46.

The spelling of 19542921616 in words is "nineteen billion, five hundred forty-two million, nine hundred twenty-one thousand, six hundred sixteen".