70892721 has 6 divisors (see below), whose sum is σ = 102400610. Its totient is φ = 47261808.

The previous prime is 70892713. The next prime is 70892729. The reversal of 70892721 is 12729807.

It is an interprime number because it is at equal distance from previous prime (70892713) and next prime (70892729).

It can be written as a sum of positive squares in only one way, i.e., 52359696 + 18533025 = 7236^2 + 4305^2 .

It is not a de Polignac number, because 70892721 - 2³ = 70892713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (70892729) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3938476 + ... + 3938493.

Almost surely, 2^70892721 is an apocalyptic number.

It is an amenable number.

70892721 is a deficient number, since it is larger than the sum of its proper divisors (31507889).

70892721 is a wasteful number, since it uses less digits than its factorization.

70892721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7876975 (or 7876972 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 36.

The square root of 70892721 is about 8419.7815292322. The cubic root of 70892721 is about 413.8731145144.

The spelling of 70892721 in words is "seventy million, eight hundred ninety-two thousand, seven hundred twenty-one".