64543890 has 16 divisors (see below), whose sum is σ = 154905408. Its totient is φ = 17211696.

The previous prime is 64543889. The next prime is 64543907. The reversal of 64543890 is 9834546.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1075702 + ... + 1075761.

It is an arithmetic number, because the mean of its divisors is an integer number (9681588).

Almost surely, 2^64543890 is an apocalyptic number.

64543890 is an abundant number, since it is smaller than the sum of its proper divisors (90361518).

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

64543890 is a wasteful number, since it uses less digits than its factorization.

64543890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2151473.

The product of its (nonzero) digits is 103680, while the sum is 39.

The square root of 64543890 is about 8033.9212094717. The cubic root of 64543890 is about 401.1299094231.

It can be divided in two parts, 645 and 43890, that multiplied together give a triangular number (28309050 = T₇₅₂₄).

The spelling of 64543890 in words is "sixty-four million, five hundred forty-three thousand, eight hundred ninety".