19749136 has 45 divisors (see below), whose sum is σ = 42479269. Its totient is φ = 8888000.

The previous prime is 19749133. The next prime is 19749137. The reversal of 19749136 is 63194791.

19749136 = T₃₈₃ + T₃₈₄ + ... + T₅₅₈.

The square root of 19749136 is 4444.

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., 18974736 + 774400 = 4356^2 + 880^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19749133) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 195486 + ... + 195586.

Almost surely, 2^19749136 is an apocalyptic number.

19749136 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

19749136 is the 4444-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19749136

19749136 is an abundant number, since it is smaller than the sum of its proper divisors (22730133).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19749136 is a wasteful number, since it uses less digits than its factorization.

19749136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232 (or 114 counting only the distinct ones).

The product of its digits is 40824, while the sum is 40.

The cubic root of 19749136 is about 270.3020670525.

The spelling of 19749136 in words is "nineteen million, seven hundred forty-nine thousand, one hundred thirty-six".