78149672 has 8 divisors (see below), whose sum is σ = 146530650. Its totient is φ = 39074832.

The previous prime is 78149657. The next prime is 78149677. The reversal of 78149672 is 27694187.

It can be written as a sum of positive squares in only one way, i.e., 66357316 + 11792356 = 8146^2 + 3434^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×78149672² = 12214742467415168, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (78149677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4884347 + ... + 4884362.

Almost surely, 2^78149672 is an apocalyptic number.

It is an amenable number.

78149672 is a deficient number, since it is larger than the sum of its proper divisors (68380978).

78149672 is a wasteful number, since it uses less digits than its factorization.

78149672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9768715 (or 9768711 counting only the distinct ones).

The product of its digits is 169344, while the sum is 44.

The square root of 78149672 is about 8840.2303137418. The cubic root of 78149672 is about 427.5389830279.

The spelling of 78149672 in words is "seventy-eight million, one hundred forty-nine thousand, six hundred seventy-two".