72143778 has 96 divisors (see below), whose sum is σ = 179656704. Its totient is φ = 19211808.

The previous prime is 72143761. The next prime is 72143803. The reversal of 72143778 is 87734127.

It is a super-2 number, since 2×72143778² = 10409449408226568, which contains 22 as substring.

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 317701 + ... + 317927.

It is an arithmetic number, because the mean of its divisors is an integer number (1871424).

Almost surely, 2^72143778 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72143778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89828352).

72143778 is an abundant number, since it is smaller than the sum of its proper divisors (107512926).

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

72143778 is a wasteful number, since it uses less digits than its factorization.

72143778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316 (or 309 counting only the distinct ones).

The product of its digits is 65856, while the sum is 39.

The square root of 72143778 is about 8493.7493487858. The cubic root of 72143778 is about 416.2934974249.

The spelling of 72143778 in words is "seventy-two million, one hundred forty-three thousand, seven hundred seventy-eight".