18961544 has 64 divisors (see below), whose sum is σ = 43545600. Its totient is φ = 7560000.

The previous prime is 18961529. The next prime is 18961559. The reversal of 18961544 is 44516981.

It is an interprime number because it is at equal distance from previous prime (18961529) and next prime (18961559).

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a junction number, because it is equal to n+sod(n) for n = 18961498 and 18961507.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 75419 + ... + 75669.

It is an arithmetic number, because the mean of its divisors is an integer number (680400).

Almost surely, 2^18961544 is an apocalyptic number.

18961544 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18961544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21772800).

18961544 is an abundant number, since it is smaller than the sum of its proper divisors (24584056).

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

18961544 is a wasteful number, since it uses less digits than its factorization.

18961544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354 (or 350 counting only the distinct ones).

The product of its digits is 34560, while the sum is 38.

The square root of 18961544 is about 4354.4855034780. The cubic root of 18961544 is about 266.6600151119.

The spelling of 18961544 in words is "eighteen million, nine hundred sixty-one thousand, five hundred forty-four".