78211970 has 8 divisors (see below), whose sum is σ = 140781564. Its totient is φ = 31284784.

The previous prime is 78211963. The next prime is 78211997. The reversal of 78211970 is 7911287.

It can be written as a sum of positive squares in 2 ways, for example, as 76755121 + 1456849 = 8761^2 + 1207^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×78211970² = 12234224502561800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78211970.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3910589 + ... + 3910608.

Almost surely, 2^78211970 is an apocalyptic number.

78211970 is a deficient number, since it is larger than the sum of its proper divisors (62569594).

78211970 is a wasteful number, since it uses less digits than its factorization.

78211970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7821204.

The product of its (nonzero) digits is 7056, while the sum is 35.

The square root of 78211970 is about 8843.7531625436. The cubic root of 78211970 is about 427.6525588906.

The spelling of 78211970 in words is "seventy-eight million, two hundred eleven thousand, nine hundred seventy".