78211975 has 18 divisors (see below), whose sum is σ = 98706480. Its totient is φ = 61467120.

The previous prime is 78211963. The next prime is 78211997. The reversal of 78211975 is 57911287.

It is not a de Polignac number, because 78211975 - 2¹⁵ = 78179207 is a prime.

It is a super-2 number, since 2×78211975² = 12234226066801250, which contains 22 as substring.

It is a hoax number, since the sum of its digits (40) 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 17 ways as a sum of consecutive naturals, for example, 392926 + ... + 393124.

Almost surely, 2^78211975 is an apocalyptic number.

78211975 is a deficient number, since it is larger than the sum of its proper divisors (20494505).

78211975 is an equidigital number, since it uses as much as digits as its factorization.

78211975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 487 (or 283 counting only the distinct ones).

The product of its digits is 35280, while the sum is 40.

The square root of 78211975 is about 8843.7534452290. The cubic root of 78211975 is about 427.6525680037.

The spelling of 78211975 in words is "seventy-eight million, two hundred eleven thousand, nine hundred seventy-five".